Fermentation

20 pages, 789 KB

Open AccessEditor’s ChoiceReview

The Metabolites Produced by Lactic Acid Bacteria and Their Role in the Microbiota–Gut–Brain Axis

by Yulma Lizbeth Aguirre-Garcia, Neftiti Carolina Cerda-Alvarez, Rosa María Santiago-Santiago, Adriana Rocío Chantre-López, Sarahi Del Carmen Rangel-Ortega and Raúl Rodríguez-Herrera

Fermentation 2025, 11(7), 378; https://doi.org/10.3390/fermentation11070378 - 30 Jun 2025

Viewed by 6302

Abstract

Lactic acid bacteria (LAB) have historically been used in fermentation processes, playing a key role in the development of foods with health benefits. Understanding the factors that affect LAB functionality is essential for optimizing their application. During fermentation processes, LAB produce different metabolites [...] Read more.

Lactic acid bacteria (LAB) have historically been used in fermentation processes, playing a key role in the development of foods with health benefits. Understanding the factors that affect LAB functionality is essential for optimizing their application. During fermentation processes, LAB produce different metabolites of interest, such as lactic acid, gamma-aminobutyric acid (GABA), and short-chain fatty acids, whose production is influenced by conditions such as temperature and pH. Although LAB exhibit optimal growth ranges, their ability to adapt to moderate variations makes them particularly valuable in various applications. Currently, the impact of these LAB metabolites on human physiology is being actively investigated, especially for modulation of the Microbiota–Gut–Brain axis. Certain compounds derived from LAB have been shown to contribute to neurological, immunological, and metabolic processes, opening new perspectives for the design of functional foods. This article provides a comprehensive overview of the importance of lactic acid bacteria in human health and highlights their potential for the development of innovative strategies to promote well-being through diet. Full article

(This article belongs to the Special Issue Feature Review Papers in Microbial Metabolism, Physiology & Genetics, 2nd Edition)

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20 pages, 1233 KB

Open AccessEditor’s ChoiceReview

Microalgal Valorization of CO₂: A Sustainable Pathway to Biofuels and High-Value Chemicals

by Shutong Wu, Kaiyin Ye, Xiaochuan Zheng and Lei Zhao

Fermentation 2025, 11(7), 371; https://doi.org/10.3390/fermentation11070371 - 27 Jun 2025

Cited by 1 | Viewed by 2292

Abstract

The escalating climate crisis and the imperative to transition from a fossil fuel-dependent economy demand transformative solutions for sustainable energy and carbon management. Biological CO₂ capture and utilization (CCU) using microalgae represents a particularly compelling approach, capitalizing on microalgae’s high photosynthetic efficiency [...] Read more.

The escalating climate crisis and the imperative to transition from a fossil fuel-dependent economy demand transformative solutions for sustainable energy and carbon management. Biological CO₂ capture and utilization (CCU) using microalgae represents a particularly compelling approach, capitalizing on microalgae’s high photosynthetic efficiency and remarkable product versatility. This review critically examines the principles and recent breakthroughs in microalgal CO₂ bioconversion, spanning strain selection, advanced photobioreactor (PBR) design, and key factors influencing carbon sequestration efficiency. We explore diverse valorization strategies, including next-generation biofuel production, integrated wastewater bioremediation, and the synthesis of value-added chemicals, underscoring their collective potential for mitigating CO₂ emissions and achieving comprehensive resource valorization. Persistent challenges, such as economically viable biomass harvesting, cost-effective scale-up, and enhancing strain robustness, are rigorously examined. Furthermore, we delineate promising future prospects centered on cutting-edge genetic engineering, integrated biorefinery concepts, and synergistic coupling with waste treatment to maximize sustainability. By effectively bridging carbon neutrality with renewable resource production, microalgae-based technologies hold considerable potential to spearhead the circular bioeconomy, accelerate the renewable energy transition, and contribute significantly to achieving global climate objectives. Full article

(This article belongs to the Special Issue Algae—The Medium of Bioenergy Conversion: 2nd Edition)

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17 pages, 1011 KB

Open AccessEditor’s ChoiceArticle

Bioprocessing of Spent Coffee Grounds as a Sustainable Alternative for the Production of Bioactive Compounds

by Karla A. Luna, Cristóbal N. Aguilar, Nathiely Ramírez-Guzmán, Héctor A. Ruiz, José Luis Martínez and Mónica L. Chávez-González

Fermentation 2025, 11(7), 366; https://doi.org/10.3390/fermentation11070366 - 26 Jun 2025

Cited by 1 | Viewed by 3933

Abstract

Spent coffee grounds are the most abundant waste generated during the preparation of coffee beverages, amounting to 60 million tons per year worldwide. Excessive food waste production has become a global issue, emphasizing the need for waste valorization through the bioprocess of solid-state [...] Read more.

Spent coffee grounds are the most abundant waste generated during the preparation of coffee beverages, amounting to 60 million tons per year worldwide. Excessive food waste production has become a global issue, emphasizing the need for waste valorization through the bioprocess of solid-state fermentation (SSF) for high added-value compounds. This work aims to identify the operational conditions for optimizing the solid-state fermentation process of spent coffee grounds to recover bioactive compounds (as polyphenols). An SSF process was performed using two filamentous fungi (Trichoderma harzianum and Rhizopus oryzae). An exploratory design based on the Hunter & Hunter method was applied to analyze the effects of key parameters such as inoculum size (spores/mL), humidity (%), and temperature (°C). Subsequently, a Box–Behnken experimental design was carried out to recovery of total polyphenols. DPPH, ABTS, and FRAP assays evaluated antioxidant activity. The maximum concentration of polyphenols was observed in treatment T3 (0.279 ± 0.002 TPC mg/g SCG) using T. harzianum, and a similar result was obtained with R. oryzae in the same treatment (0.250 ± 0.011 TPC mg/g SCG). In the Box–Behnken design, the most efficient treatment for T. harzianum was T12 (0.511 ± 0.017 TPC mg/g SCG), and for R. oryzae, T9 (0.636 ± 0.003 TPC mg/g SCG). These extracts could have applications in the food industry to improve preservation and functionality. Full article

(This article belongs to the Special Issue Valorization of Food Waste Using Solid-State Fermentation Technology)

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19 pages, 1446 KB

Open AccessEditor’s ChoiceReview

Postbiotics Derived from Lactic Acid Bacteria Fermentation: Therapeutic Potential in the Treatment of Muscular Complications in Inflammatory Bowel Disease

by Emili Bruna Toso Bueno, Kimberlly de Oliveira Silva, Maria Eduarda Ferraz Mendes, Lívia Batista de Oliveira, Felipe Prado de Menezes, Anna Cardoso Imperador, Lucimeire Fernandes Correia and Lizziane Kretli Winkelstroter

Fermentation 2025, 11(7), 362; https://doi.org/10.3390/fermentation11070362 - 23 Jun 2025

Cited by 2 | Viewed by 3382

Abstract

Inflammatory bowel disease (IBD) is characterized by chronic inflammation in the gastrointestinal tract, which can result in several muscular complications, including sarcopenia, the loss of muscle mass, and impaired muscle function. Recently, postbiotics derived from lactic bacteria, such as Lactobacillus and Bifidobacterium, [...] Read more.

Inflammatory bowel disease (IBD) is characterized by chronic inflammation in the gastrointestinal tract, which can result in several muscular complications, including sarcopenia, the loss of muscle mass, and impaired muscle function. Recently, postbiotics derived from lactic bacteria, such as Lactobacillus and Bifidobacterium, have emerged as potential therapeutic modulators for these complications. Postbiotics are bioactive metabolites, such as short-chain fatty acids (SCFAs), antimicrobial peptides, and other compounds produced by microorganisms during fermentation, which have anti-inflammatory, antioxidant, and metabolic regulatory effects. These metabolites are important due to their potential to positively influence muscle health in patients with IBD, mainly by reducing systemic and local inflammation, improving gut microbiota, and modulating muscle metabolism. Studies suggest that these postbiotics may help minimize muscle degradation and promote muscle tissue regeneration, assisting in the prevention or management of IBD-associated sarcopenia. Despite the promising results, challenges remain, such as variability in postbiotic production and the need for further clinical studies to establish clear therapeutic guidelines. This review article explores the mechanisms of action of postbiotics derived from lactic acid bacteria and their potential applications in the treatment of muscle complications in patients with IBD, highlighting future therapeutic perspectives. Full article

(This article belongs to the Topic News and Updates on Probiotics)

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29 pages, 2053 KB

Open AccessEditor’s ChoiceSystematic Review

Benefits of Kombucha Consumption: A Systematic Review of Clinical Trials Focused on Microbiota and Metabolic Health

by Gabriela Macedo Fraiz, Dandara Baia Bonifácio, Rayanne Santos de Paulo, Carolynne Martins Teixeira, Hércia Stampini Duarte Martino, Frederico Augusto Ribeiro de Barros, Fermín I. Milagro and Josefina Bressan

Fermentation 2025, 11(6), 353; https://doi.org/10.3390/fermentation11060353 - 17 Jun 2025

Cited by 1 | Viewed by 15591

Abstract

Background: Fermented foods rich in bioactive compounds have been proposed as potential strategy to combat non-communicable diseases. Among them is kombucha, a beverage fermented from sugared Camellia sinensis tea by a symbiotic culture of bacteria and yeasts (SCOBY). Recently, there has been an [...] Read more.

Background: Fermented foods rich in bioactive compounds have been proposed as potential strategy to combat non-communicable diseases. Among them is kombucha, a beverage fermented from sugared Camellia sinensis tea by a symbiotic culture of bacteria and yeasts (SCOBY). Recently, there has been an increased focus on assessing the actual effect of this beverage on human health. In this manner, this systematic review aimed to gather clinical evidence on the impact of kombucha consumption on human health. Methods: The databases Cochrane CENTRAL, MEDLINE/PubMed, and Embase^® were searched, and the risk of bias tool used was the Critical Appraisal Tools outlined in the Joanna Briggs Institute. This review followed the PRISMA guidelines and was registered on PROSPERO (CRD42024599464). Results: Eight clinical trials were included (two pre- and post-interventions and six randomized controlled trials) with durations ranging from 10 days to 10 weeks. Two studies reported beneficial effects of kombucha on gastrointestinal symptoms, such as reduced intensity of constipation-related complaints. Two trials observed changes in gut microbiota composition, including increased abundance in Bacteroidota, Akkermansiaceae, Saccharomyces, and Weizmannia coagulans, alongside reductions in Ruminococcus, Dorea, and Rhodotorula. Moreover, five clinical trials evaluated glucose metabolism, evidencing inconsistent results, and other studies identified improvements in salivary microbiota composition and serum metabolomic profile. Conclusion: These findings suggest that kombucha consumption may provide health benefits, particularly in alleviating gastrointestinal symptoms, and demonstrates a modest capacity for modulating gut and salivary microbiota, as well as metabolomic profiles. Although the results are promising, the heterogeneity of the studies and the limited number of available clinical trials highlight the need for further robust research to confirm these effects. Full article

(This article belongs to the Special Issue Fermentation and Bioactive Potential of Kombucha and Bee-Derived Compounds for Health and Wellness)

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12 pages, 528 KB

Open AccessEditor’s ChoiceArticle

Probiotic Potential of Lactic Acid Bacteria Strains Isolated from Artisanal Cheeses: Impact on Listeria monocytogenes Infection

by Carla Burgos, Constanza Melian, Lucía M. Mendoza, Susana Salva and Patricia Castellano

Fermentation 2025, 11(6), 343; https://doi.org/10.3390/fermentation11060343 - 12 Jun 2025

Cited by 1 | Viewed by 1410

Abstract

Listeriosis is a disease associated with the consumption of food contaminated with Listeria monocytogenes. Probiotic lactic acid bacteria (LAB) or their postbiotics have been of interest for their anti-listerial effect. This study focused on isolating LAB from artisanal cheeses and characterizing their [...] Read more.

Listeriosis is a disease associated with the consumption of food contaminated with Listeria monocytogenes. Probiotic lactic acid bacteria (LAB) or their postbiotics have been of interest for their anti-listerial effect. This study focused on isolating LAB from artisanal cheeses and characterizing their potential as probiotics. Twelve LAB isolates exhibiting typical LAB traits were evaluated for their ability to survive in simulated gastric juice, hydrolyze bile salts, auto-aggregate, hydrophobicity, and antagonistic activity against L. monocytogenes. The four most promising LAB strains demonstrated anti-listerial probiotic potential and were identified as Latilactobacillus (Lat.) curvatus SC076 and Lactiplantibacillus (Lact.) paraplantarum SC291, SC093, and SC425. The antimicrobial activity of these strains was mainly attributed to bacteriocin-like substances and organic acids. While three Lact. paraplantarum strains were resistant to ampicillin, Lat. curvatus was sensitive to all tested antibiotics. All selected strains exhibited no hemolytic, gelatinase, and lecithinase activity. Exposure to LAB supernatants resulted in a significant reduction in the adhesion and intracellular count of L. monocytogenes in Caco-2 cells, with Lat. curvatus SC076 showing the most significant effect. Based on its probiotic characteristics, Lat. curvatus SC076 is a promising candidate for functional foods, pending further in vivo studies to assess its potential in the food industry. Full article

(This article belongs to the Special Issue Lactic Acid Bacteria: Evaluation of Benefits on Human Health and Improvement of Food Safety)

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35 pages, 3228 KB

Open AccessEditor’s ChoiceReview

A Review of Sensors for the Monitoring, Modeling, and Control of Commercial Wine Fermentations

by Roger Boulton, James Nelson and André Knoesen

Fermentation 2025, 11(6), 329; https://doi.org/10.3390/fermentation11060329 - 7 Jun 2025

Cited by 1 | Viewed by 6296

Abstract

Large-scale commercial wine fermentation requires the monitoring and control of multiple variables to achieve optimal results. Challenges in measurement arise from turbidity, stratification in large unmixed volumes, the presence of grape skins and solids during red wine fermentations, the small changes in variables [...] Read more.

Large-scale commercial wine fermentation requires the monitoring and control of multiple variables to achieve optimal results. Challenges in measurement arise from turbidity, stratification in large unmixed volumes, the presence of grape skins and solids during red wine fermentations, the small changes in variables that necessitate precise sensors, and the unique composition of each juice, which makes every fermentation distinct. These complications contribute to nonlinear and time-variant characteristics for most control variables. This paper reviews sensors, particularly online ones, utilized in commercial winemaking. It examines the measurement of solution properties (density, weight, volume, osmotic pressure, dielectric constant, and refractive index), sugar consumption, ethanol and glycerol production, redox potential, cell mass, and cell viability during wine fermentation and their relevance as variables that could enhance the estimation of parameters in diagnostic and predictive wine fermentation models. Various methods are compared based on sensitivity, availability of sensor systems, and their appropriateness for measuring properties in large commercial wine fermentations. Additionally, factors influencing the adoption of control strategies are discussed. Finally, potential opportunities for control strategies and challenges for future sensor developments are outlined. Full article

(This article belongs to the Section Fermentation for Food and Beverages)

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13 pages, 1412 KB

Open AccessEditor’s ChoiceArticle

Harnessing Raman Spectroscopy for Enhanced Bioprocess Monitoring: Predictive CO₂ Analysis and Robust pH Determination in Bioreactor Off-Gas Stream

by Tobias Wallocha and Michaela Poth

Fermentation 2025, 11(6), 317; https://doi.org/10.3390/fermentation11060317 - 2 Jun 2025

Viewed by 3781

Abstract

The accurate measurement of CO₂ concentration in fermentation off-gas is crucial for monitoring and optimizing bioprocesses, particularly in mammalian cell cultures. In this study, we successfully utilized Raman off-gas spectroscopy to achieve time-resolved prediction of CO₂ concentrations in the fermentation off-gas. [...] Read more.

The accurate measurement of CO₂ concentration in fermentation off-gas is crucial for monitoring and optimizing bioprocesses, particularly in mammalian cell cultures. In this study, we successfully utilized Raman off-gas spectroscopy to achieve time-resolved prediction of CO₂ concentrations in the fermentation off-gas. Our experiments were conducted using two different media: a commercial medium (medium 1) and an in-house Roche medium (medium 2), each tested with two different lots. The results demonstrated that Raman spectroscopy provides precise and real-time CO₂ measurements, which are essential for effective process monitoring and control. Furthermore, we established that CO₂ off-gas analysis can be directly correlated with the pH value of the fermentation medium. This correlation allows for accurate pH prediction with comparable precision to traditional methods, where CO₂ levels are first determined via Raman spectroscopy or an off-gas analyzer and then used to infer pH through a correlation curve. In the final step of our study, we employed a Raman submers probe to predict CO₂ and pH directly within the fermentation medium. Compared to the model accuracy in the off-gas stream, the performance of the Raman submers probe in predicting CO₂ and pH within the medium was significantly worse, likely due to the absence of a pretrained model for CO₂. Our findings highlight the potential of Raman off-gas spectroscopy as a powerful tool for real-time bioprocess monitoring and control, offering significant advantages in terms of accuracy and efficiency. Full article

(This article belongs to the Special Issue Strategies for Optimal Fermentation by Using Modern Tools and Methods, 2nd Edition)

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30 pages, 1170 KB

Open AccessEditor’s ChoiceReview

Biofuel–Pharmaceutical Co-Production in Integrated Biorefineries: Strategies, Challenges, and Sustainability

by Tao Liu, Miaoxin He, Rui Shi, Hui Yin and Wen Luo

Fermentation 2025, 11(6), 312; https://doi.org/10.3390/fermentation11060312 - 30 May 2025

Cited by 3 | Viewed by 3216

Abstract

Global demands for sustainable energy and advanced therapeutics necessitate innovative interdisciplinary solutions. Integrated biorefining emerges as a strategic response, enabling the co-production of biofuels and pharmaceutical compounds through biomass valorization. This integrated model holds promise in enhancing resource utilization efficiency while ensuring economic [...] Read more.

Global demands for sustainable energy and advanced therapeutics necessitate innovative interdisciplinary solutions. Integrated biorefining emerges as a strategic response, enabling the co-production of biofuels and pharmaceutical compounds through biomass valorization. This integrated model holds promise in enhancing resource utilization efficiency while ensuring economic viability. Our critical review methodically evaluates seven pivotal methodologies: seven key strategies: microbial metabolites, synthetic biology platforms, biorefinery waste extraction, nanocatalysts, computer-aided design, extremophiles, and plant secondary metabolites. Through systematic integration of these approaches, we reveal pivotal synergies and potential technological innovations that can propel multi-product biorefinery systems. Persistent challenges, particularly in reconciling complex metabolic flux balancing with regulatory compliance requirements, are analyzed. Nevertheless, advancements in systems biology, next-generation bioprocess engineering, and artificial intelligence-enhanced computational modeling present viable pathways for overcoming these obstacles. This comprehensive analysis substantiates the transformative capacity of integrated biorefining in establishing a circular bioeconomy framework, while underscoring the imperative of transdisciplinary cooperation to address existing technical and policy constraints. Full article

(This article belongs to the Special Issue Biofuels and Green Technology)

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17 pages, 2382 KB

Open AccessEditor’s ChoiceArticle

Effects of Co-Fermentation with Lactic Acid Bacteria and Yeast on Gliadin Degradation in Whole-Wheat Sourdough

by Daiva Zadeike, Kamile Cipkute and Dalia Cizeikiene

Fermentation 2025, 11(5), 238; https://doi.org/10.3390/fermentation11050238 - 23 Apr 2025

Cited by 3 | Viewed by 2135

Abstract

This study investigates the potential of utilising the proteolytic activity of two different strains, Levilactobacillus brevis FST140 and Pediococcus pentosaceus FST22, to assess their impact on wheat gluten proteins. A high-power ultrasound (US) treatment (850 kHz; 500 W/cm²; 35 °C) was [...] Read more.

This study investigates the potential of utilising the proteolytic activity of two different strains, Levilactobacillus brevis FST140 and Pediococcus pentosaceus FST22, to assess their impact on wheat gluten proteins. A high-power ultrasound (US) treatment (850 kHz; 500 W/cm²; 35 °C) was used to activate the proteolytic system of LAB to promote gliadin-like protein degradation in wheat wholemeal-based sourdough. The proteolytic activity of L. brevis and P. pentosaceus increased two-fold with 10 and 20 min US stimulation, respectively, compared to fermentation without ultrasonication. Regarding the impact of proteolysis and sonication on gliadin proteins, fermentation with both strains reduced gliadin content in commercial gluten by an average of 77.4% compared to the untreated sample, and additional US treatment further enhanced gliadin degradation efficiency to an average of 83.5%. The combined application of US and lactic acid fermentation initiated a seven-fold decrease in wheat wholemeal flour (WF) gliadin levels compared to the untreated sample (47.2 mg/g). Furthermore, the synergistic application of US, LAB, and yeast fermentation allowed us to reduce gliadin content up to 1.6 mg/g, as well as to reduce gluten content in the sourdough up to 3 mg/g. Despite complete hydrolysis of the gliadin fraction under the combined effects of US and fermentation, glutenins were less affected by the applied treatments in all cases. The technology presented in this study offers a promising approach for producing gluten-free or low-gluten fermented products in the bread-making industry. Full article

(This article belongs to the Special Issue Bioactive Compounds in Grain Fermentation: 2nd Edition)

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50 pages, 1219 KB

Open AccessEditor’s ChoiceReview

Bioactive Properties of Fermented Beverages: Wine and Beer

by Vanesa Postigo, Margarita García, Julia Crespo, Laura Canonico, Francesca Comitini and Maurizio Ciani

Fermentation 2025, 11(5), 234; https://doi.org/10.3390/fermentation11050234 - 22 Apr 2025

Cited by 8 | Viewed by 6574

Abstract

In recent years, consumer demand has been increasingly oriented to fermented foods and/or beverages with functional properties. The functional beverage industry focused on producing a product that combines a peculiar aromatic taste with healthy properties. Today’s consumers are trying to reduce alcohol, gluten, [...] Read more.

In recent years, consumer demand has been increasingly oriented to fermented foods and/or beverages with functional properties. The functional beverage industry focused on producing a product that combines a peculiar aromatic taste with healthy properties. Today’s consumers are trying to reduce alcohol, gluten, sugar, and carbohydrates in beer and wine without reducing their native taste. Wine and beer are among the world’s most consumed beverages, and several studies confirm that fermented beverages could be associated with beneficial properties for human health. All beneficial properties derive both from the fermentation process and also from the characteristics of the raw materials used in the two beverages. This review was conducted to highlight the importance of the fermentative microorganisms in wine and beer and their relationship with functional foods, underlining their involvement in human health. Full article

(This article belongs to the Special Issue Biotechnological and Functional/Probiotic Characteristics of Non-Conventional Yeasts in Fermented Beverages)

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12 pages, 445 KB

Open AccessEditor’s ChoiceArticle

Development and Production of High-Oleic Palm Oil Alternative by Fermentation of Microalgae

by Leon Parker, Kevin Ward, Thomas Pilarski, James Price, Paul Derkach, Mona Correa, Roberta Miller, Veronica Benites, Dino Athanasiadis, Bryce Doherty, Lucy Edy, Gawharah Alnozaili, Nina Reyes, Jon Wittenberg, Gener Eliares, Frédéric Destaillats, Walter Rakitsky and Scott Franklin

Fermentation 2025, 11(4), 207; https://doi.org/10.3390/fermentation11040207 - 10 Apr 2025

Cited by 2 | Viewed by 2993

Abstract

The development of high-oleic palm oil alternatives through microbial fermentation offers a sustainable solution to the environmental challenges associated with traditional palm oil cultivation. In this study, a Prototheca moriformis microalgae strain was optimized via classical strain improvement techniques to produce a high-oleic [...] Read more.

The development of high-oleic palm oil alternatives through microbial fermentation offers a sustainable solution to the environmental challenges associated with traditional palm oil cultivation. In this study, a Prototheca moriformis microalgae strain was optimized via classical strain improvement techniques to produce a high-oleic palm oil with fatty acid and triacylglycerol (TAG) profiles similar to those of conventional high-oleic palm oil. Iterative rounds of mutagenesis and screening enhanced the palmitic acid content from 28 to 30–32% and oleic acid from 60 to 55–57% of total fatty acids, with an oil yield of 136.5 g/L and an oil content of 69.45% of the dry cell weight. The scalability of this process was demonstrated across fermentation scales ranging from 1 L to 50 L. The TAG profile showed elevated unsaturated TAG species, meeting the quality and nutritional requirements of industrial applications. These findings highlight the potential of microbial systems to address the growing demand for high-value nutritional oils while alleviating the environmental and socio-economic impacts of tropical oil crop cultivation. The application of P. moriformis fermentation provides a transformative approach to advancing sustainability and resilience in global fat and oil production. Full article

(This article belongs to the Special Issue Algae—The Medium of Bioenergy Conversion: 2nd Edition)

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23 pages, 3482 KB

Open AccessEditor’s ChoiceArticle

Eco-Friendly Biosurfactant: Tackling Oil Pollution in Terrestrial and Aquatic Ecosystems

by Kaio Wêdann Oliveira, Alexandre Augusto P. Selva Filho, Yslla Emanuelly S. Faccioli, Gleice Paula Araújo, Attilio Converti, Rita de Cássia F. Soares da Silva and Leonie A. Sarubbo

Fermentation 2025, 11(4), 199; https://doi.org/10.3390/fermentation11040199 - 8 Apr 2025

Cited by 3 | Viewed by 2024

Abstract

Spills involving fuels and lubricating oils in industrial environments caused by the fueling of machines, inadequate storage and the washing of equipment are significant sources of environmental pollution, impacting soil and water bodies. Such incidents alter the microbiological, chemical and physical properties of [...] Read more.

Spills involving fuels and lubricating oils in industrial environments caused by the fueling of machines, inadequate storage and the washing of equipment are significant sources of environmental pollution, impacting soil and water bodies. Such incidents alter the microbiological, chemical and physical properties of affected environments. The use of biosurfactants is an effective option for the cleaning of storage tanks and the remediation of contaminated soils and effluents. The scope of this work was to assess the production and application of a Starmerella bombicola ATCC 22214 biosurfactant to remediate marine and terrestrial environment polluted by oil. The production of the biosurfactant was optimized in terms of carbon/nitrogen sources and culture conditions using flasks. The performance of the biosurfactant was tested in clayey soil, silty soil, and standard sand, as well as smooth surfaces and industrial effluents contaminated with oils (fuel oils B1 for thermal power generation, diesel, and motor oil). The ideal culture medium for the production of the biosurfactant contained 2% glucose and 5% glycerol, with agitation at 200 rpm, fermentation for 180 h and a 5% inoculum, resulting in a yield of 1.5 g/L. The biosurfactant had high emulsification indices (86.6% for motor oil and 51.7% for diesel) and exhibited good stability under different pH values, temperatures and concentrations of NaCl. The critical micelle concentration was 0.4 g/L, with a surface tension of 26.85 mN/m. In remediation tests, the biosurfactant enabled the removal of no less than 99% of motor oil from different types of soil. The results showed that the biosurfactant produced by Starmerella bombicola is a promising agent for the remediation of environments contaminated by oil derivatives, especially in industrial environments and for the treatment of oily effluents. Full article

(This article belongs to the Special Issue Use of Agro-Industrial Waste and By-Products for the Sustainable Production of Eco-Friendly Surface-Active Compounds)

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27 pages, 4827 KB

Open AccessEditor’s ChoiceTechnical Note

Design and Operation of a Multifunctional Pilot-Scale Bioreactor for Enhanced Aerobic Fermentation

by Mauro Moresi

Fermentation 2025, 11(2), 101; https://doi.org/10.3390/fermentation11020101 - 17 Feb 2025

Cited by 4 | Viewed by 6190

Abstract

The primary aim of this work was to share the results from a Research Project supported by the Italian National Research Council, which led to the development of a versatile jacketed tower bioreactor. Designed to optimize oxygen transfer efficiency and process control, the [...] Read more.

The primary aim of this work was to share the results from a Research Project supported by the Italian National Research Council, which led to the development of a versatile jacketed tower bioreactor. Designed to optimize oxygen transfer efficiency and process control, the reactor incorporated a reciprocating air compressor, centrifugal pumps, a draft tube with or without perforated plates, and a series of gas–liquid ejectors. Its flexible design enabled operation in both airlift and ejector-loop modes, making it suitable for a wide range of aerobic fermentation processes. By sharing the detailed engineering design, operational procedures of this pilot-scale bioreactor, as well as its performance data when cultivating yeasts on whey and potato wastewater, a detailed blueprint was given to researchers seeking to advance bioreactor technology, particularly in the context of emerging fields like cultured meat production, pharmaceutical manufacturing, and environmental bioremediation. Full article

(This article belongs to the Section Fermentation Process Design)

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15 pages, 4205 KB

Open AccessEditor’s ChoiceArticle

Lacticaseibacillus paracasei LT12—A Probiotic Strain That Reduces Hyperuricemia via Inhibiting XO Activity and Regulating Renal Uric Acid Transportation Protein

by Wei-Ting Tseng, Xiang-Ru Kong, Yu-Tsung Han, Wen-Yang Lin, Deyi Yin, Lei Du, Jingli Xie and Tien-Hung Chang

Fermentation 2025, 11(2), 96; https://doi.org/10.3390/fermentation11020096 - 13 Feb 2025

Cited by 2 | Viewed by 2189

Abstract

Hyperuricemia (HUA), characterized by elevated serum uric acid (UA) levels, is a key risk factor for gout. In human purine metabolism, approximately 70% of UA is excreted via the kidneys, while the remaining 30% is eliminated through the intestines. Thus, the intestinal microbiota [...] Read more.

Hyperuricemia (HUA), characterized by elevated serum uric acid (UA) levels, is a key risk factor for gout. In human purine metabolism, approximately 70% of UA is excreted via the kidneys, while the remaining 30% is eliminated through the intestines. Thus, the intestinal microbiota plays a crucial role in regulating UA metabolism through the gut–kidney axis. However, the detailed mechanisms by which the microbiota reduces serum UA levels and supports kidney health remain unclear. In this study, researchers investigated the potential of Lacticaseibacillus paracasei LT12, a strain exhibiting xanthine oxidase (XO) inhibition activity and the ability to degrade inosine and guanosine, in reducing UA levels in a hyperuricemia mouse model. Hyperuricemia was induced by gavaging mice with 300 mg/kg of potassium oxonate and hypoxanthine for two weeks. The subsequent 4-week intervention included five groups: a normal control group, a model group, a positive control group receiving allopurinol (5 mg/kg body weight), a low-dose LT12 group (1.5 × 10⁶ CFU/kg), and a high-dose LT12 group (4.5 × 10⁹ CFU/kg). The results demonstrated that L. paracasei LT12 effectively reduced serum UA levels, inhibited serum and hepatic XO activity, regulated renal uric acid transporter proteins (OAT1, URAT1, GLUT9, and ABCG2), and reduced the abundance of the intestinal pathogenic bacterium Corynebacterium stationis in both the low-dose and high-dose groups. Notably, only the high-dose LT12 group significantly increased gut butyrate levels. In conclusion, L. paracasei LT12 shows promise as a potential probiotic strain for ameliorating hyperuricemia. Future human clinical studies are needed to validate its efficacy. Full article

(This article belongs to the Special Issue Lactic Acid Fermentation and the Colours of Biotechnology: 4th Edition)

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21 pages, 3549 KB

Open AccessEditor’s ChoiceArticle

Two-Stage Bioconversion of Cellulose to Single-Cell Protein and Oil via a Cellulolytic Consortium

by Eric Charles Peterson, Christian Hermansen, Ashriel Yong, Rowanne Siao, Gi Gi Chua, Sherilyn Ho, Coleen Toledo Busran, Megan Teo, Aaron Thong, Melanie Weingarten and Nic Lindley

Fermentation 2025, 11(2), 72; https://doi.org/10.3390/fermentation11020072 - 2 Feb 2025

Cited by 2 | Viewed by 2643

Abstract

A novel approach for converting non-edible plant biomass into single-cell protein and oil (SCPO) via consolidated bioprocessing has been established, leveraging aerotolerant thermophilic cellulolytic consortia consisting mainly of Thermoanaerobacterium thermosaccharolyticum, Sporolactobacillus spp. and Clostridium sensu stricto to achieve the rapid and complete [...] Read more.

A novel approach for converting non-edible plant biomass into single-cell protein and oil (SCPO) via consolidated bioprocessing has been established, leveraging aerotolerant thermophilic cellulolytic consortia consisting mainly of Thermoanaerobacterium thermosaccharolyticum, Sporolactobacillus spp. and Clostridium sensu stricto to achieve the rapid and complete conversion of crystalline cellulose into a consistent cocktail of lactate, acetate and ethanol. This cocktail is an excellent substrate for cultivating organisms for SCPO production and food and feed applications, including Cyberlindnera jadinii, Yarrowia lipolytica and Corynebacterium glutamicum. Cultivation on this cocktail resulted in yields (Y_X/S) of up to 0.43 ± 0.012 g/g, indicating a yield from cellulose (Y_X/Cellulose) of up to 0.27 ± 0.007 g/g (dwb). The resulting SCPO was rich in protein (42.5% to 57.9%), essential amino acids (27.8% to 43.2%) and lipids (7.9% to 8.4%), with unsaturated fatty acid fractions of up to 89%. Unlike fermentation feedstocks derived from easily digested feedstocks (i.e., food waste), this approach has been applied to cellulosic biomass, and this mixed-culture bioconversion can be carried out without adding expensive enzymes. This two-stage cellulosic bioconversion can unlock non-edible plant biomass as an untapped feedstock for food and feed production, with the potential to strengthen resiliency and circularity in food systems. Full article

(This article belongs to the Special Issue Lignocellulosic Biomass Valorization)

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13 pages, 6214 KB

Open AccessEditor’s ChoiceArticle

Elucidating the Connection Between the Health-Promoting Properties of Limosilactobacillus fermentum Lf2 and Its Exopolysaccharides

by Elisa C. Ale, Analía Ale, Guillermo H. Peralta, José M. Irazoqui, Gabriela Correa Olivar, Victoria Allende Roldán, Gabriel Vinderola, Ariel F. Amadio, Carina V. Bergamini, Jimena Cazenave and Ana G. Binetti

Fermentation 2025, 11(2), 69; https://doi.org/10.3390/fermentation11020069 - 1 Feb 2025

Viewed by 1407

Abstract

The potential probiotic properties of Limosilactobacillus fermentum Lf2, an exopolysaccharide (EPS)-producing strain, were assessed in C57BL/6 mice. The aim of this work was to elucidate if these properties could be associated with the ability to produce EPSs. Mice were divided into three treatments: [...] Read more.

The potential probiotic properties of Limosilactobacillus fermentum Lf2, an exopolysaccharide (EPS)-producing strain, were assessed in C57BL/6 mice. The aim of this work was to elucidate if these properties could be associated with the ability to produce EPSs. Mice were divided into three treatments: L (mice treated with Lf2), E (animals that received EPSs), and C (control group). The levels of fecal acetic and propionic acids significantly increased in L and E compared with C. Catalase activity increased in L in comparison with the other groups in the liver and small intestine. The enzyme activities of superoxide dismutase and glutathione S-transferase increased in the large intestine for L compared with C. In addition, in the large intestine, the concentration of TNF-α was reduced in L and E in comparison with C. In the small intestine, TNF-α, IFN-γ, IL-12, and IL-6 presented lower levels in L and E than C. The analysis of the gut microbiota showed that L presented higher levels of Peptococcaceae and Rikenellaceae, while E had higher levels of Peptococcaceae than C. Overall, these results provide new insights into the relationship between the probiotic properties of lactic acid bacteria and their ability to produce EPSs. Full article

(This article belongs to the Special Issue Lactic Acid Bacteria: Evaluation of Benefits on Human Health and Improvement of Food Safety)

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28 pages, 6080 KB

Open AccessEditor’s ChoiceArticle

Meat-Processing Wastewater Treatment Using an Anaerobic Membrane Bioreactor (AnMBR)

by Ferdinand Hummel, Lisa Bauer, Wolfgang Gabauer and Werner Fuchs

Fermentation 2025, 11(2), 68; https://doi.org/10.3390/fermentation11020068 - 1 Feb 2025

Cited by 1 | Viewed by 3248

Abstract

This study explores AnMBR technology as a promising method for treating wastewater from the meat-processing industry by analysing its characteristics and impact under continuous feeding. The solids were retained, utilising an ultrafiltration membrane with a pore size of 0.2 µm, and the efficacy [...] Read more.

This study explores AnMBR technology as a promising method for treating wastewater from the meat-processing industry by analysing its characteristics and impact under continuous feeding. The solids were retained, utilising an ultrafiltration membrane with a pore size of 0.2 µm, and the efficacy of reducing the organic load was evaluated. Although the COD removal rate decreased from 100% at an OLR of 0.71 g/(L*d) to 73% at an OLR of 2.2 g/(L*d), maximum methane yields were achieved at the highest OLR, 292.9 Nm³/t (COD) and 397.8 Nm³/t (VS) per loaded organics and 353.1 Nm³/t (COD) and 518.7 Nm³/t (VS) per removed organics. An analysis of the microbial community was performed at the end of the experiment to assess the effects of the process and the substrate on its composition. The AnMBR system effectively converts meat-processing wastewater into biogas, maintaining high yields and reducing the loss of dissolved methane in the permeate, thanks to a temperature of 37 °C and high salt levels. AnMBR enables rapid start-up, efficient COD removal, and high biogas yields, making it suitable for treating industrial wastewater with high organic loads, enhancing biogas production, and reducing methane loss. Challenges such as high salt and phosphate levels present opportunities for a wider use in nutrient recovery and water reclamation. Full article

(This article belongs to the Special Issue Food Wastes: Feedstock for Value-Added Products: 5th Edition)

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27 pages, 2817 KB

Open AccessEditor’s ChoiceArticle

A Novel Wild-Type Lacticaseibacillus paracasei Strain Suitable for the Production of Functional Yoghurt and Ayran Products

by Ioanna Prapa, Chrysoula Pavlatou, Vasiliki Kompoura, Anastasios Nikolaou, Electra Stylianopoulou, George Skavdis, Maria E. Grigoriou and Yiannis Kourkoutas

Fermentation 2025, 11(1), 37; https://doi.org/10.3390/fermentation11010037 - 17 Jan 2025

Cited by 3 | Viewed by 3341

Abstract

Raw goat and ewe’s milk samples were used for the isolation of seven lactic acid bacteria new strains. After testing hemolytic activity and resistance to antibiotics, specific functional properties were evaluated; Lactococcus lactis subsp. lactis FBM_1321 and Lacticaseibacillus paracasei FBM_1327 strains resulted in [...] Read more.

Raw goat and ewe’s milk samples were used for the isolation of seven lactic acid bacteria new strains. After testing hemolytic activity and resistance to antibiotics, specific functional properties were evaluated; Lactococcus lactis subsp. lactis FBM_1321 and Lacticaseibacillus paracasei FBM_1327 strains resulted in the highest cholesterol assimilation percentages ranging from 28.78 to 30.56%. In addition, strong adhesion capacity to differentiated Caco-2 cells (1.77–21.04%) was mapped, and the lactobacilli strains exhibited strong antagonistic activity against foodborne pathogens compared to lactococci. The strains were able to grow at low pH and high NaCl concentrations, conditions that prevail in food systems (cell counts ranged from 1.77 to 8.48 log CFU/mL after exposure to pH 3 and from 5.66 to 9.52 log CFU/mL after exposure to NaCl concentrations up to 8%). As a next step, freeze-dried immobilized Lc. paracasei FBM_1327 cells on oat flakes were used for the preparation of functional yoghurt and ayran products. Cell loads of the functional strain remained high and stable in both products (7.69 log CFU/g in yoghurt and 8.56 log CFU/g in ayran after 30 days of storage at 4 °C) throughout their shelf life. No significant changes in the volatile profile were noticed, and the new products were accepted by the panel during the sensory evaluation. Full article

(This article belongs to the Special Issue Lactic Acid Fermentation and the Colours of Biotechnology: 4th Edition)

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18 pages, 2454 KB

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Carbon Dioxide Micro-Nano Bubbles Aeration Improves Carbon Fixation Efficiency for Succinic Acid Synthesis by Escherichia coli

by Ying Chen, Hao Wu, Qianqian Huang, Jingwen Liao, Liuqing Wang, Yue Pan, Anming Xu, Wenming Zhang and Min Jiang

Fermentation 2025, 11(1), 31; https://doi.org/10.3390/fermentation11010031 - 14 Jan 2025

Viewed by 2180

Abstract

The low solubility of CO₂ in water leads to massive CO₂ emission and extremely low CO₂ utilization in succinic acid (SA) biosynthesis. To enhance microbial CO₂ utilization, micro-nano bubbles (MNBs) were induced in SA biosynthesis by E. coli Suc260 [...] Read more.

The low solubility of CO₂ in water leads to massive CO₂ emission and extremely low CO₂ utilization in succinic acid (SA) biosynthesis. To enhance microbial CO₂ utilization, micro-nano bubbles (MNBs) were induced in SA biosynthesis by E. coli Suc260 in this study. The results showed that MNB aeration decreased CO₂ emissions and increased CO₂ solubility in the medium significantly. The CO₂ utilization of MNB aeration was 129.69% higher than that of bubble aeration in atmospheric fermentation. However, MNBs showed a significant inhibitory effect on bacterial growth in the pressurized environment, although a two-stage aerobic–anaerobic fermentation strategy weakened the inhibition. The biofilm-enhanced strain E. coli Suc260-CsgA showed a strong tolerance to MNBs. In pressurized fermentation with MNB aeration, the actual CO₂ utilization of E. coli Suc260-CsgA was 30.63% at 0.18 MPa, which was a 6.49-times improvement. The CO₂ requirement for SA synthesis decreased by 83.4%, and the fugitive emission of CO₂ was successfully controlled. The activities of key enzymes within the SA synthesis pathway were also maintained or enhanced in the fermentation process with MNB aeration. These results indicated that the biofilm-enhanced strain and CO₂-MNBs could improve carbon fixation efficiency in microbial carbon sequestration. Full article

(This article belongs to the Section Fermentation Process Design)

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24 pages, 10488 KB

Open AccessEditor’s ChoiceArticle

Meta-Omics Analyses of Conventional and Regenerative Fermented Vegetables: Is There an Impact on Health-Boosting Potential?

by Kylene Guse, Qingqing Mao, Chi Chen and Andres Gomez

Fermentation 2025, 11(1), 22; https://doi.org/10.3390/fermentation11010022 - 7 Jan 2025

Viewed by 2314

Abstract

Fermented vegetables contain probiotic microbes and metabolites, which are transformed from fresh vegetables, potentially providing health benefits. The kind of vegetable used to ferment and how it is grown may determine the types of health-promoting properties. To understand the possible benefits of fermented [...] Read more.

Fermented vegetables contain probiotic microbes and metabolites, which are transformed from fresh vegetables, potentially providing health benefits. The kind of vegetable used to ferment and how it is grown may determine the types of health-promoting properties. To understand the possible benefits of fermented vegetables under different growing conditions, we compared the microbiomes and metabolomes of three different types of naturally fermented vegetables—carrots, peppers, and radishes—that were grown either under conventional or regenerative growing systems. We profiled bacterial and fungal communities via 16S rRNA short-read (V4 region), long-read, and ITS2 sequencing, in tandem with untargeted metabolomics (LC-MS). The results showed that the microbiomes and metabolomes of the fermented vegetables under each growing system are unique, highlighting distinctions in amino acid content and potentially probiotic microbes (p < 0.05). All fermented vegetables contained high amounts of gamma-aminobutyric acid (GABA), a critical neurotransmitter. However, GABA was found to be in higher abundance in the regenerative fermented vegetables, particularly in carrots (p < 0.01) and peppers (p < 0.05), and was associated with higher abundances of the typically probiotic Lactiplantibacillus plantarum. Our findings indicate that the growing system may impact the microbiome and metabolome of plant-based ferments, encouraging more research on the health-boosting potential of regeneratively grown vegetables. Full article

(This article belongs to the Special Issue Advances in Fermented Fruits and Vegetables)

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16 pages, 2261 KB

Open AccessEditor’s ChoiceArticle

Extractive Ethanol Fermentation with Ethanol Recovery by Absorption in Open and Closed Systems

by Kaio César da Silva Rodrigues, Ivan Ilich Kerbauy Veloso, Diego Andrade Lemos, Antonio José Gonçalves Cruz and Alberto Colli Badino

Fermentation 2025, 11(1), 12; https://doi.org/10.3390/fermentation11010012 - 2 Jan 2025

Viewed by 3115

Abstract

Conventional ethanol production has limitations, including substrate and product inhibitions, which increase both energy requirements for ethanol recovery and vinasse generation. Extractive fermentation, which removes ethanol as it is produced within the fermentation vat, offers an effective alternative to reducing the inhibitory effects [...] Read more.

Conventional ethanol production has limitations, including substrate and product inhibitions, which increase both energy requirements for ethanol recovery and vinasse generation. Extractive fermentation, which removes ethanol as it is produced within the fermentation vat, offers an effective alternative to reducing the inhibitory effects in conventional processes. However, an efficient method for recovering the extracted ethanol is also crucial. Thus, this study investigated an alternative ethanol production process using extractive ethanol fermentation integrated with ethanol recovery by absorption in both open and closed systems, specifically, comparing scenarios with and without CO₂ recirculation produced during fermentation. The recovery system used two absorbers connected in series using monoethylene glycol (MEG) as an absorbent. Under extractive fermentation conditions without CO₂ recirculation, the conversion of 300.0 g L⁻¹ of substrate resulted in a total ethanol concentration of 135.2 g L⁻¹, which is 68% higher than that achieved in conventional fermentation (80.4 g L⁻¹). The absorption recovery efficiency reached 91.6%. In the closed system, with CO₂ recirculation produced by fermentation, 280.0 g L⁻¹ of substrate was consumed, achieving ethanol production of 126.0 g L⁻¹, with an absorption recovery percentage of 98.3%, similar to that of industrial facilities that use a gas scrubber tower. Additionally, the overall process efficiency was close to that of conventional fermentation (0.448 g_ethanol g_substrate⁻¹). These results highlight the potential of this alternative process to reduce vinasse volume and energy consumption for ethanol recovery, lowering total costs and making it a viable option for integrated distilleries that combines ethanol production with other related processing operations. Full article

(This article belongs to the Special Issue Bioprocesses for Biomass Valorization in Biorefineries)

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27 pages, 6525 KB

Open AccessEditor’s ChoiceArticle

Unveiling the Microbial Symphony of Amasi: A Targeted Metagenomic 16S rRNA, ITS, and Metabolites Insights Using Bovine and Caprine Milk

by Betty Olusola Ajibade, Titilayo Adenike Ajayeoba, Saheed Sabiu, Konstantin V. Moiseenko, Sizwe Vincent Mbona, Errol D. Cason, Tatyana V. Fedorova and Oluwatosin Ademola Ijabadeniyi

Fermentation 2025, 11(1), 6; https://doi.org/10.3390/fermentation11010006 - 31 Dec 2024

Cited by 1 | Viewed by 2974

Abstract

Amasi, a traditional fermented milk produced in Southern Africa, is associated with several health benefits, such as probiotic activities, immune system modulation, and pharmacological (antimicrobial, antitumor and antioxidant) potential. This study investigated the microbial diversity in Amasi (produced from cow’s and goat’s milk) [...] Read more.

Amasi, a traditional fermented milk produced in Southern Africa, is associated with several health benefits, such as probiotic activities, immune system modulation, and pharmacological (antimicrobial, antitumor and antioxidant) potential. This study investigated the microbial diversity in Amasi (produced from cow’s and goat’s milk) through targeted metagenomic bacterial 16S rRNA and fungal ITS sequencing, the metabolic functional prediction of Amasi samples using the Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) and profiled amino acids constituents using Liquid Chromatographic-Mass Spectrophotometry (LC-MS). The results obtained revealed Firmicutes, Bacteroidetes, and Proteobacteria as the most prevalent bacterial phyla, with Lactococcus and Lactobacillus being the most abundant genera. On the other hand, Ascomycota, Basidiomycota, and Mucoromycota were the main fungal phyla, while Aspergillus, Kazachstania, and Debaryomyces spp. dominated the fungal genera. Also, Pseudomonas spp., Bacillus spp., Clostridium spp., Cronobacter spp., Alternaria spp., Diaporthe spp., and Penicillium spp. were the probable pathogenic bacteria and fungi genera found, respectively. Atopobium, Synechococcus, and Parabacteroides were found less often as rare genera. It was found that the amino acid and drug metabolism pathway prediction values in Amasi samples were significantly higher (p < 0.05) than in raw cow and goat milk, according to the inferred analysis (PICRUSt). The amino acid validation revealed glutamine and asparagine values as the most significant (p < 0.05) for Amasi cow milk (ACM) and Amasi goat milk (AGM), respectively. Comparatively, ACM showed more microbial diversity than AGM, though there were relative similarities in their microbiome composition. PICRUSt analysis revealed significant metabolites in the two Amasi samples. Overall, data from this study showed heterogeneity in microbial diversity, abundance distributions, metabolites, and amino acid balance between raw cow/goat milk and Amasi samples. Full article

(This article belongs to the Special Issue Dairy Fermentation, 3rd Edition)

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17 pages, 4018 KB

Open AccessEditor’s ChoiceArticle

Isolation and Identification of Novel Non-Dairy Starter Culture Candidates from Plant Matrix Using Backslopping Propagation

by Maret Andreson, Jekaterina Kazantseva, Aili Kallastu, Taaniel Jakobson, Inga Sarand and Mary-Liis Kütt

Fermentation 2024, 10(12), 663; https://doi.org/10.3390/fermentation10120663 - 23 Dec 2024

Cited by 1 | Viewed by 2315

Abstract

The majority of non-dairy starter cultures on the market are originally isolated from milk and therefore do not provide the most optimal fermentation for plant matrices. Developing plant-derived starter cultures is essential for creating high-quality, tasty dairy alternatives. This study aims to isolate [...] Read more.

The majority of non-dairy starter cultures on the market are originally isolated from milk and therefore do not provide the most optimal fermentation for plant matrices. Developing plant-derived starter cultures is essential for creating high-quality, tasty dairy alternatives. This study aims to isolate and characterize bacterial strains with the potential to be used as non-dairy starters from plant sources via backslopping evolution. A natural consortium of macerated plants was inoculated into two oat and two pea commercial drinks and backslopped for seventeen cycles to evolve the bacterial consortium at 25 °C, 34 °C, and 42 °C. The results showed that the initial natural consortium contained less than 1% lactic acid bacteria, and after the seventeenth cycle, lactic acid bacteria dominated in all investigated consortia. Oat Od1-25 and Od2-42 and pea Pd1-34 and Pd1-42 samples were selected for strain isolation based on amplicon-based metagenetic analysis of 16S rRNA gene sequencing and sensory properties. The strain isolation was performed using an out-plating technique, and colonies were identified by MALDI-TOF mass spectrometry. Altogether, eleven lactic acid bacteria species of plant origin were obtained. The strains belonged to the Leuconostoc, Enterococcus, Lactobacillus, and Lactococcus genera. Full article

(This article belongs to the Special Issue Microbiota and Metabolite Changes in Fermented Foods)

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21 pages, 886 KB

Open AccessEditor’s ChoiceArticle

Machine Learning Prediction of Foaming in Anaerobic Co-Digestion from Six Key Process Parameters

by Sarah E. Daly and Ji-Qin Ni

Fermentation 2024, 10(12), 639; https://doi.org/10.3390/fermentation10120639 - 13 Dec 2024

Cited by 3 | Viewed by 1976

Abstract

Foaming in co-digested anaerobic digesters can reduce biogas production, leading to economic loss. However, the underlying causes of foaming are not completely understood. This study investigated a field-scale mesophilic digester system that experienced intermittent foaming, employing experimental and modeling methods over a 16-month [...] Read more.

Foaming in co-digested anaerobic digesters can reduce biogas production, leading to economic loss. However, the underlying causes of foaming are not completely understood. This study investigated a field-scale mesophilic digester system that experienced intermittent foaming, employing experimental and modeling methods over a 16-month period. Samples were collected during both foaming and non-foaming events and were thoroughly characterized for methane (CH₄) yields and different physical and chemical concentrations, including volatile solids (VS), metals, total phosphorus (TP), total chemical oxygen demand (TCOD), total volatile fatty acids (TVFAs), and total alkalinity (TALK). Machine learning techniques were applied to predict foaming events with several algorithms tested to optimize prediction accuracy. The results showed that digester liquid and effluent samples collected from foaming events had significantly lower (p < 0.05) average CH₄ yields (77 and 45 mL CH₄ g VS⁻¹) than during non-foaming events (150 and 83 mL CH₄ g VS⁻¹). Recursive feature modeling identified six key parameters (1. Fe(II):S; 2. Fe(II):TP; 3. TCOD; 4. Fe; 5. TVFA:TALK; and 6. Cu) associated with digester foaming. Among the tested machine learning models, the support vector machine (SVM) algorithm achieved the highest recognition accuracy of 87%. This study demonstrates that the interactions of multiple chemical and physical process parameters are an important consideration for predicting anaerobic digester foaming. Full article

(This article belongs to the Section Fermentation Process Design)

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17 pages, 3258 KB

Open AccessEditor’s ChoiceArticle

Bioconversion of Agro-Industrial Byproducts Using Bacillus sp. CL18: Production of Feather Hydrolysates for Development of Bioactive Polymeric Nanofibers

by Naiara Jacinta Clerici, Daniel Joner Daroit, Aline Aniele Vencato and Adriano Brandelli

Fermentation 2024, 10(12), 615; https://doi.org/10.3390/fermentation10120615 - 30 Nov 2024

Cited by 2 | Viewed by 1904

Abstract

Microbial fermentation represents an interesting strategy for the management and valorization of agro-industrial byproducts. In this study, the proteolytic strain Bacillus sp. CL18 was used to produce bioactive hydrolysates during submerged cultivation with various protein-containing substrates, including byproducts from the poultry (feathers), cheese [...] Read more.

Microbial fermentation represents an interesting strategy for the management and valorization of agro-industrial byproducts. In this study, the proteolytic strain Bacillus sp. CL18 was used to produce bioactive hydrolysates during submerged cultivation with various protein-containing substrates, including byproducts from the poultry (feathers), cheese (whey), fish (scales), and vegetable oil (soybean meal) industries. The bioactive feather hydrolysates (BFHs) showing high antioxidant activity were incorporated in poly(vinyl alcohol) (PVA) and poly-ε-caprolactone (PCL) nanofibers by the electrospinning technique. The PVA nanofibers containing 5% BFH reached antioxidant activities of 38.7% and 76.3% for DPPH and ABTS assays, respectively. Otherwise, the PCL nanofibers showed 49.6% and 55.0% scavenging activity for DPPH and ABTS radicals, respectively. Scanning electron microscopy analysis revealed that PVA and PCL nanofibers containing BFH had an average diameter of 282 and 960 nm, respectively. Moreover, the results from thermal analysis and infrared spectroscopy showed that the incorporation of BFH caused no significant modification in the properties of the polymeric matrix. The bioconversion of feathers represents an interesting strategy for the management and valorization of this byproduct. Furthermore, the effective incorporation of BFH in polymeric nanofibers and validation of the biological activity suggest the application of these materials as antioxidant coatings and packaging. Full article

(This article belongs to the Special Issue Waste as Feedstock for Fermentation)

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14 pages, 1896 KB

Open AccessEditor’s ChoiceArticle

Efficient Two-Stage Meso- and Thermophilic Anaerobic Digestion of Food Waste from a Microbial Perspective

by Katsuaki Ohdoi, Yoshihiro Okamoto, Tomonori Koga, Haruka Takahashi, Mugihito Oshiro, Toshihito Morimitsu, Hideki Muraoka, Yukihiro Tashiro and Kenji Sakai

Fermentation 2024, 10(12), 607; https://doi.org/10.3390/fermentation10120607 - 28 Nov 2024

Cited by 2 | Viewed by 3114

Abstract

Two-stage meso- and thermophilic anaerobic digestion (TSMTAD) of food waste was examined and its microbiological structure was investigated. The first stage was designed for the primary storage of perishable food waste and the second stage for central biogas production. Mesophilic storage with initial [...] Read more.

Two-stage meso- and thermophilic anaerobic digestion (TSMTAD) of food waste was examined and its microbiological structure was investigated. The first stage was designed for the primary storage of perishable food waste and the second stage for central biogas production. Mesophilic storage with initial neutralization and inoculation of lactic acid bacteria (LAB) resulted in an accumulation of lactic acid (21–23 g/L) with a decreased pH, in which bacterial members in facultative hetero-fermentation-type LAB dominated. Repeated fed-batch storage showed stable accumulation of lactic acid, retaining 89.3% (av.) carbon and preventing the growth of exogenous food pathogens. When the second stage of TSMTAD was compared with direct single-stage anaerobic digestion (SSAD) at 55 °C, the amount of methane accumulated was 1.48-fold higher (896 NmL/g-vs.). The methane yield of the original food refuse was 6.9% higher in the case of TSMTAD. The microbial community structures of both cases were similar, consisting of a sole thermophilic hydrogen-assimilating methanogen, Methanothermobacter thermautotrophicus. However, the abundance of bacteria belonging to two functional groups, H₂ CO₂ and acetic acid producer, and syntrophic acetate-oxidizing bacteria increased in TSMTAD. This may change the metabolic pathway, contributing to the stimulation of methane productivity. Full article

(This article belongs to the Special Issue Anaerobic Digestion: Waste to Energy: 2nd Edition)

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11 pages, 735 KB

Open AccessEditor’s ChoiceArticle

Development and Large-Scale Production of High-Oleic Acid Oil by Fermentation of Microalgae

by Leon Parker, Kevin Ward, Thomas Pilarski, James Price, Paul Derkach, Mona Correa, Roberta Miller, Veronica Benites, Dino Athanasiadis, Bryce Doherty, Lucy Edy, Gawharah Alnozaili, Nina Reyes, Jon Wittenberg, Gener Eliares, Frédéric Destaillats, Walter Rakitsky and Scott Franklin

Fermentation 2024, 10(11), 566; https://doi.org/10.3390/fermentation10110566 - 6 Nov 2024

Cited by 6 | Viewed by 3892

Abstract

Our classical strain improvement began with an isolate showing 28% palmitic and 60% oleic acids. UV and chemical mutagenesis enhanced our strain’s productivity, carbon yield, and oleic acid content. The iterative methodology we used involved the creation of mutant libraries followed by clonal [...] Read more.

Our classical strain improvement began with an isolate showing 28% palmitic and 60% oleic acids. UV and chemical mutagenesis enhanced our strain’s productivity, carbon yield, and oleic acid content. The iterative methodology we used involved the creation of mutant libraries followed by clonal isolation, assessments of feedstock utilization and growth, oil titer, and the validation of oil composition. Screening these libraries facilitated the identification of isolates with the ability to produce elevated levels of oleic acid, aligning with the targets for high-oleic acid substitutes. Utilizing a classical strain improvement approach, we successfully isolated a high-oleic acid strain wherein the level of oleic acid was increased from 60 to >86% of total FA. The performance of the classically improved high oleic acid-producing strain was assessed at fermentation scales ranging from 1 L to 4000 L, demonstrating the utility of our strain and process at an industrial scale. These oils offer promise in various applications across both the food and industrial sectors, with the added potential of furthering sustainability and health-conscious initiatives. Full article

(This article belongs to the Special Issue Precision Fermentation: Applications in the Food and Beverage Industry)

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12 pages, 1505 KB

Open AccessEditor’s ChoiceArticle

Constructing a New Pathway for Ethylene Glycol Biosynthesis and Its Coenzyme Reuse Mechanism

by Zeyang Zhu, Wenwei Li, Dan Wang, Xia Fang, Jianing Li and Xuyang Li

Fermentation 2024, 10(11), 558; https://doi.org/10.3390/fermentation10110558 - 31 Oct 2024

Viewed by 3051

Abstract

As a high-value bulk chemical, ethylene glycol plays an important role in many fields such as energy, the chemical industry, and automobile manufacturing. At the same time, methanol, as an economical and efficient raw material, has shown great potential in promoting the innovation [...] Read more.

As a high-value bulk chemical, ethylene glycol plays an important role in many fields such as energy, the chemical industry, and automobile manufacturing. At the same time, methanol, as an economical and efficient raw material, has shown great potential in promoting the innovation of bio-based chemicals and fuels. In view of this, this study focused on the excavation and innovative application of enzymes, and successfully designed an efficient artificial cascade catalytic system. The system cleverly converts methanol into ethylene glycol, and the core is composed of methanol dehydrogenase, glycolaldehyde synthase, and lactoaldehyde–pyruvate oxidoreductase. The three enzyme systems work together, which not only simplifies the metabolic pathway, but also realizes the efficient reuse of coenzymes. Subsequently, after ribosome-binding site (RBS) optimization, isopropyl β-D-Thiogalactoside (IPTG) induction regulation, and methanol concentration adjustment, the concentration of ethylene glycol reached 14.73 mM after 48 h of reaction, and the conversion rate was 58.92%. Furthermore, a new breakthrough in ethylene glycol production was achieved within 48 h by using a two-stage biotransformation strategy and fed-batch feeding in a 5 L fermentor, reaching 49.29 mM, which is the highest yield of ethylene glycol reported so far. This achievement not only opens up a new way for the biotransformation of ethylene glycol, but also lays a foundation for the industrial application in this field in the future. Full article

(This article belongs to the Special Issue Fermentation: 10th Anniversary)

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17 pages, 3805 KB

Open AccessEditor’s ChoiceArticle

Predicting the Microbiome and Metabolome Dynamics of Natural Apple Fermentation Towards the Development of Enhanced Functional Vinegar

by Bruna Leal Maske, Ignácio Ruiz, Alexander da Silva Vale, Vitória de Mello Sampaio, Najua Kêmil El Kadri, Carlos Ricardo Soccol and Gilberto Vinícius Pereira

Fermentation 2024, 10(11), 552; https://doi.org/10.3390/fermentation10110552 - 30 Oct 2024

Cited by 2 | Viewed by 4130

Abstract

Natural vinegar fermentation is a complex process influenced by the interplay between microbial communities and metabolites. This study examined the interplay between the microbiome and the metabolome over a three-month period, with samples collected every ten days. Using Illumina sequencing and chromatographic techniques [...] Read more.

Natural vinegar fermentation is a complex process influenced by the interplay between microbial communities and metabolites. This study examined the interplay between the microbiome and the metabolome over a three-month period, with samples collected every ten days. Using Illumina sequencing and chromatographic techniques (HPLC and GC-MS), we mapped microbial shifts and metabolite profiles. Early fermentation showed a diverse microbial presence, including genera such as Cronobacter, Luteibacter, and Saccharomyces. A stable microbial ecosystem established between days 15 and 70, characterized by the dominance of Leuconostoc, Gluconobacter, and Saccharomyces, which facilitated consistent substrate consumption and metabolite production, including various organic acids and ethanol. By day 70, Acetobacter prevalence increased significantly, correlating with a peak acetic acid production of 12.4 g/L. Correlation analyses revealed significant relationships between specific microbes and volatile organic compounds. This study highlights the crucial roles of these microbes in developing sensory profiles suited for industrial applications and proposes an optimal microbial consortium for enhancing vinegar quality. These data suggest that an optimal microbial consortium for vinegar fermentation should include Saccharomyces for efficient alcohol production, Leuconostoc for ester-mediated flavor complexity, and Acetobacter for robust acetic acid production. The presence of Komagataeibacter could further improve the sensory and functional qualities due to its role in producing bacterial cellulose. Full article

(This article belongs to the Special Issue Functional Properties of Microorganisms in Fermented Foods)

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23 pages, 2662 KB

Open AccessEditor’s ChoiceArticle

The Combined Effect of Four Nutraceutical-Based Feed Additives on the Rumen Microbiome, Methane Gas Emission, Volatile Fatty Acids, and Dry Matter Disappearance Using an In Vitro Batch Culture Technique

by Kelechi A. Ike, Deborah O. Okedoyin, Joel O. Alabi, Oludotun O. Adelusi, Michael Wuaku, Lydia K. Olagunju, Chika C. Anotaenwere, DeAndrea Gray, Peter A. Dele, Ahmed E. Kholif, Misty D. Thomas and Uchenna Y. Anele

Fermentation 2024, 10(10), 499; https://doi.org/10.3390/fermentation10100499 - 28 Sep 2024

Cited by 3 | Viewed by 1710

Abstract

This study aimed to investigate the effect of an essential oil/fumaric combination, mannan-oligosaccharide, galactooligosaccharide, and a mannan-oligosaccharide/galactooligosaccharide combination on the dry matter disappearance (DMD), gas production, greenhouse gasses, volatile fatty acid, and microbial community of a total mixed ration using a 24 [...] Read more.

This study aimed to investigate the effect of an essential oil/fumaric combination, mannan-oligosaccharide, galactooligosaccharide, and a mannan-oligosaccharide/galactooligosaccharide combination on the dry matter disappearance (DMD), gas production, greenhouse gasses, volatile fatty acid, and microbial community of a total mixed ration using a 24 h in vitro batch culture technique. The study design was a completely randomized design with four treatments as follows: a control treatment without any additives, the control treatment supplemented with galactooligosaccharide at 3% (Gos treatment), a galactooligosaccharide and mannan-oligosaccharide mixture at 1:1 at 3% (Gosmos treatment), or an essential oil blend (200 μL/g feed) and fumaric acid at 3% combination (Eofumaric treatment). The Gosmos treatment had the highest (p < 0.05) DMD (63.8%) and the numerical lowest acetate–propionate ratio (p = 0.207), which was 36.9% higher compared to the control. The lowest Shannon index, Simpson’s index, and all the diversity indices were recorded for the Eofumaric treatment, while the other treatments had similar Shannon index, Simpson’s index, and diversity index. The Z-score differential abundance between the Eofumaric and the control indicated that the inclusion of the Eofumaric treatment differentially increased the abundance of Patescibacteria, Synergistota, Chloroflexi, Actinobacteriota, Firmicutes, and Euryarchaeota while Verrucomicrobiota, WPS-2, Fibrobacterota, and Spirochaetota were decreased. The Random Forest Classification showed that the lower relative abundance of Fibrobacterota, Spirochaetota, and Elusimicrobiota and the higher relative abundance of Firmicutes and Chloroflexi were most impactful in explaining the microbial community data. Overall, the essential oil blend showed great potential as a methane gas mitigation strategy by modifying rumen fermentation through changes in the microbial community dynamics. Full article

(This article belongs to the Section Fermentation Process Design)

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11 pages, 2230 KB

Open AccessEditor’s ChoiceArticle

Neutral Red Film Augments Extracellular Electron Transfer Performed by Clostridium pasteurianum DSM 525

by Ana Clara Bonizol Zani, João Carlos de Souza, Adalgisa Rodrigues de Andrade and Valeria Reginatto

Fermentation 2024, 10(10), 497; https://doi.org/10.3390/fermentation10100497 - 27 Sep 2024

Cited by 2 | Viewed by 1814

Abstract

Extracellular electron transfer (EET) is key to the success of microbial fuel cells (MFCs). Clostridium sp. often occurs in MFC anode communities, but its ability to perform EET remains controversial. We have employed Clostridium pasteurianum DSM 525 as a biocatalyst in a glycerol-fed [...] Read more.

Extracellular electron transfer (EET) is key to the success of microbial fuel cells (MFCs). Clostridium sp. often occurs in MFC anode communities, but its ability to perform EET remains controversial. We have employed Clostridium pasteurianum DSM 525 as a biocatalyst in a glycerol-fed MFC, designated MFC_DSM. We have also followed the EET of this biocatalyst in the presence of a mediator, namely soluble neutral red (NR), soluble methyl viologen (MV), neutral red film (FNR), or methyl viologen film (FMV). MFC_DSM provided power and current densities (j) of 0.39 μW·cm⁻² and 2.47 μA·cm⁻², respectively, which evidenced that the biocatalyst performs direct electron transfer (DET). Introducing 150.0 µM NR or MV into the MFC_DSM improved the current density by 7.0- and 3.7-fold (17.05 and 8.45 μA·cm⁻²), respectively. After 20 cyclic voltammetry (CV) cycles, the presence of FNR in the MFC_DSM anodic chamber provided an almost twofold higher current density (30.76 µA·cm⁻²) compared to the presence of NR in the MFC_DSM. Introducing MV or FMV into the MFC_DSM anodic chamber gave practically the same current density after 10 CV cycles. The MFC_DSM anodic electrode might interact with FMV weakly than with FNR, so FNR is more promising to enhance C. pasteurianum DSM 525 EET within MFC_DSM. Full article

(This article belongs to the Special Issue Microbial Fuel Cell Advances)

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13 pages, 2228 KB

Open AccessEditor’s ChoiceArticle

Growth of Lactiplantibacillus plantarum BG112 in Batch and Continuous Culture with Camellia sinensis as Prebiotic

by Óscar Ariel Rojas-Rejón, Carlos Gonzalez-Figueredo, Ana Ruth Quintero-Covarrubias and Alejandro Saldaña-Jáuregui

Fermentation 2024, 10(9), 487; https://doi.org/10.3390/fermentation10090487 - 19 Sep 2024

Cited by 3 | Viewed by 4738

Abstract

This work aimed to study the effect of Camellia sinensis extract (CSExt) as a particular growth promoter of Lactiplantibacillus plantarum (LP) in batch and continuous production processes. Growth conditions were 1% (v/v) inoculum, pH_C = 6.5, 1% of [...] Read more.

This work aimed to study the effect of Camellia sinensis extract (CSExt) as a particular growth promoter of Lactiplantibacillus plantarum (LP) in batch and continuous production processes. Growth conditions were 1% (v/v) inoculum, pH_C = 6.5, 1% of dissolved oxygen (D.O.), 37 °C, and 150 rpm in a 0.2 L bioreactor using a commercial MRS broth (de Man, Rogosa, and Sharpe) and 1% (v/v) or 10% (v/v) CSExt according to the experimental design. In batch experiments, the maximum specific growth rate and the affinity constant increased with the increase in CSExt. In continuous culture, biomass production increased significantly with the addition of 1% (w/v) CSExt at 0.15 (1/h). Kinetic parameters adjusted were similar to those reported in the literature. Substrate affinity and the specific growth rate increased significantly in the presence of CSExt in batch and continuous cultures. Based on the results, prebiotics from plant extracts may function as growth promoters in specific physiological stages. This is the first report showing the change in kinetic parameters of a probiotic strain growing in crude plant extracts. Full article

(This article belongs to the Section Probiotic Strains and Fermentation)

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16 pages, 2634 KB

Open AccessEditor’s ChoiceArticle

A New Concept for the Rapid Development of Digital Twin Core Models for Bioprocesses in Various Reactor Designs

by André Moser, Christian Appl, Ralf Pörtner, Frank Baganz and Volker C. Hass

Fermentation 2024, 10(9), 463; https://doi.org/10.3390/fermentation10090463 - 6 Sep 2024

Cited by 5 | Viewed by 3906

Abstract

In this research work, a new software tool concept and its application for the rapid and flexible development of mechanistic digital twin core models for bioprocesses in various reactor designs are presented. The newly developed software tool concept automatically combines user-selected submodels into [...] Read more.

In this research work, a new software tool concept and its application for the rapid and flexible development of mechanistic digital twin core models for bioprocesses in various reactor designs are presented. The newly developed software tool concept automatically combines user-selected submodels into an overall digital twin core model. The main part is a biokinetic submodel, of which three were designed for enzymatic, microbial and biocatalytic processes, which can be adapted to specific processes. Furthermore, the digital twin core model contains a physico-chemical submodel (e.g., calculating pH or oxygen transfer) and a reactor submodel. The basis of the reactor submodel is an ideally mixed stirred tank reactor. The biokinetic submodel is decoupled from the reactor submodels and enables an independent parameterisation of submodels. Connecting ideally mixed stirred tank reactor models allows for the simulation of different reactor designs. The implementation of an executable digital twin core model was accelerated, creating a new software tool concept. When the concept was applied, the development time and the computing time of digital twin core models for the cultivation of Saccharomyces cerevisiae in two coupled stirred tank reactors as well as for enzymatic hydrolysis processes in a packed-bed reactor were reduced by 90%. Full article

(This article belongs to the Special Issue Fermentation Processes: Modeling, Optimization and Control: 2nd Edition)

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15 pages, 627 KB

Open AccessEditor’s ChoiceArticle

Effect of Skimmed Milk Powder and Fruit Jams Addition on the Physicochemical Characteristics of Yogurt

by Simona Janoušek Honesová, Eva Samková, Eva Dadáková, Lucie Hasoňová, Markéta Jarošová, Karolína Reindl and Jan Bárta

Fermentation 2024, 10(9), 462; https://doi.org/10.3390/fermentation10090462 - 5 Sep 2024

Cited by 2 | Viewed by 3802

Abstract

In three consecutive experiments, natural yogurt (NY) and fruit yogurt (FY) fortified with 5 and 10% skimmed milk powder (SMP) and 10% jam from black currant (BC), elderberry (EB), and their mixture of 1:1 (BCEB) were analyzed, and consumer acceptance was assessed. In [...] Read more.

In three consecutive experiments, natural yogurt (NY) and fruit yogurt (FY) fortified with 5 and 10% skimmed milk powder (SMP) and 10% jam from black currant (BC), elderberry (EB), and their mixture of 1:1 (BCEB) were analyzed, and consumer acceptance was assessed. In Experiment 1, the effect of SMP (0, 5, and 10%) on selected physicochemical parameters of the NY was evaluated. With the increasing addition of SMP, a decrease in fat content (up to −19%) and, conversely, an increase in protein content (up to +82%) and viscosity were noted. Analyses of fruits and jams intended for yogurt fortification revealed a significantly higher vitamin C content in BC than in EB and higher anthocyanins in EB than in BC. In Experiment 2, NY with 5 and 10% SMP was fortified with 10% jams (BC or EB). A joint effect of SMP and the type of fruit jam was evaluated. The same trends in fat and protein contents as in Experiment 1 were detected. The sensory evaluation showed better acceptance of FY with 10% SMP and no differences between BC and EB perception. Thus, for Experiment 3, FY was prepared with only 10% SMP and 10% jam (BC, EB, BCEB). Significant differences were detected in active acidity and color measured in the CIELab system. These results were also confirmed in sensory evaluation. The overall acceptability showed that FY with different types of jam did not significantly differ. The launching of innovative fortified yogurt onto the market represents a promising way to increase the diversity of fermented dairy products with nutritionally desirable properties. Full article

(This article belongs to the Special Issue Trends in the Development and Use of Fermented Dairy Products, 2nd Edition)

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11 pages, 484 KB

Open AccessEditor’s ChoiceArticle

Artisanal Cream Cheese Fermented with Kefir Grains

by Denise Rossi Freitas, Eliana Setsuko Kamimura and Mônica Roberta Mazalli

Fermentation 2024, 10(8), 420; https://doi.org/10.3390/fermentation10080420 - 13 Aug 2024

Cited by 5 | Viewed by 3173

Abstract

This is the first study that investigates the effect of kefir with an emphasis on the production of short-chain fatty acids (SCFAs) during the fermentation process in food products. The products developed and characterized were an artisanal cream cheese without cream and one [...] Read more.

This is the first study that investigates the effect of kefir with an emphasis on the production of short-chain fatty acids (SCFAs) during the fermentation process in food products. The products developed and characterized were an artisanal cream cheese without cream and one with added cream, and for the analysis of the fatty acid profile, both cream cheeses were compared with commercial cream cheese. The artisanal cream cheese had a high amount of lactic acid bacteria characterizing the product formed by Lactobacilli and a low concentration of lactose due to the fermentation process. Compared to commercial cream cheese, our products without and with added cream had a higher concentration of short-chain fatty acids (SCFAs), especially butyric acid, which is important for the health of the gastrointestinal tract, omega 3, and oleic fatty acid, which has been associated with the prevention and control of some diseases. Overall, the artisanal cream cheese cream with fermented cream with kefir grains is a functional product with an innovative character compared to current products on the market and was well accepted by the younger public. This new product comes as an option for those who need to change their eating habits and maintain a healthy lifestyle. Full article

(This article belongs to the Topic Fermented Food: Health and Benefit)

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17 pages, 2515 KB

Open AccessEditor’s ChoiceArticle

Thermal Treatment and Fermentation of Legume Flours with Leuconostoc citreum TR116 for the Development of Spreadable Meat Alternatives

by Aylin W. Sahin, Ophélie Gautheron and Sandra Galle

Fermentation 2024, 10(8), 412; https://doi.org/10.3390/fermentation10080412 - 9 Aug 2024

Cited by 1 | Viewed by 2484

Abstract

The demand for meat alternatives in different forms is increasing due to consumers’ awareness of climate change and the health benefits of plant-based ingredients compared to animals. However, current alternatives on the market do not fulfil consumers’ acceptance for taste and texture. Hence, [...] Read more.

The demand for meat alternatives in different forms is increasing due to consumers’ awareness of climate change and the health benefits of plant-based ingredients compared to animals. However, current alternatives on the market do not fulfil consumers’ acceptance for taste and texture. Hence, different physical and biological processes, such as thermal treatment and fermentation, need to be investigated. This study reveals that the thermal treatment of legume flours (soy, pea and lentil) prior to single-strain fermentation with Leuconostoc citreum TR116 has a major impact on acidification, colour, texture and sensory properties due to the pregelatinisation of starch and denaturation of proteins. The thermal treatment of soy flour resulted in liquification, and it could not be used as a fermentation substrate. However, non-heat-treated soy flour was fermented for comparison. The highest total titratable acidity (TTA) was determined in fermented pea flour (PF) and fermented lentil flour (LF) after 48 h with 24.35 ± 0.29 mL 0.1 M NaOH/10 g and 24.98 ± 0.33 mL 0.1 M NaOH/10 g, respectively. Heat treatment prior to fermentation led to a reduction in TTA by 20 mL 0.1 M NaOH/10 g for both PF and LF. The loss of colour pigments during thermal treatment led to a lighter colour of the spreadable alternatives. Moreover, a harder texture (+13.76 N in LF; +15.13 N in PF) and a lower adhesiveness (−0.88 N in LF; −0.43 N in PF) were detected in spreadable meat alternatives that were treated with heat prior to fermentation. Cohesiveness was decreased by thermal treatment, and fermentation did not impact it. Fermentation without pre-heat treatment increased adhesiveness by 4.37 N in LF and by 2.36 N in PF—an attribute typical for spreadable meat. Descriptive sensory analysis showed that thermal treatment significantly decreased bitterness but increased crumbliness and reduced juiciness. On the other hand, fermentation without pre-heat treatment mainly influenced flavour by increasing fruitiness and decreasing beaniness, earthiness and off-flavours. In summary, thermal treatment prior to fermentation is powerful in reducing legume-typical off-flavours but is not suitable for the development of spreadable meat alternatives due to texture changes. However, this process can be very beneficial when producing sausage-like alternatives. Full article

(This article belongs to the Special Issue Strategies for Optimal Fermentation by Using Modern Tools and Methods)

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19 pages, 1313 KB

Open AccessEditor’s ChoiceArticle

The Impact of Varying Levels of Laurus nobilis Leaves as a Sustainable Feed Additive on Ruminal Fermentation: In Vitro Gas Production, Methane and Carbon Dioxide Emissions, and Ruminal Degradability of a Conventional Diet for Ruminants

by Ahmed E. Kholif

Fermentation 2024, 10(8), 387; https://doi.org/10.3390/fermentation10080387 - 28 Jul 2024

Cited by 6 | Viewed by 2197

Abstract

The experiment aimed to evaluate the effects of varying levels of Laurus nobilis leaves [0% (control), 0.5%, 1%, 1.5%, and 2%] on the in vitro ruminal fermentation of a ruminant diet consisting of a 50% concentrate mixture, 40% berseem hay (Trifolium alexandrinum [...] Read more.

The experiment aimed to evaluate the effects of varying levels of Laurus nobilis leaves [0% (control), 0.5%, 1%, 1.5%, and 2%] on the in vitro ruminal fermentation of a ruminant diet consisting of a 50% concentrate mixture, 40% berseem hay (Trifolium alexandrinum), and 10% rice straw (Oryza sativa). The in vitro incubation lasted 48 h, during which gas production (GP), methane (CH₄), carbon dioxide (CO₂), total and individual short-chain fatty acids (SCFA), and nutrient degradability were measured. The experiment utilized a randomized block design and consisted of two incubation runs. Gas chromatography analysis revealed that 1,8-cineole (81%) was the primary volatile compound in the L. nobilis leaves. The 0.5% inclusion level exhibited the highest (linear, p = 0.006) asymptotic GP and lowest lag of GP (linear, p = 0.002), while the 2% inclusion level had the highest lag of GP. The 2% inclusion level significantly lowered CH₄ (linear, p = 0.003) compared to the control, and all levels of the leaves linearly decreased in the proportional CH₄ production (p = 0.001), with the lowest value at the 0.5% inclusion level. The highest asymptotic CO₂ production was observed with the 0.5% inclusion level (linear, p = 0.002), while the 0.5%, 1%, and 1.5% inclusion levels significantly increased (quadratic, p = 0.006) the proportion of CO₂ compared to the control. The 0.5% inclusion level showed the highest (p < 0.001) degradable DM and fiber fractions compared to the control, whereas the 2% level decreased them. The 0.5% inclusion level resulted in the highest (p < 0.01) production of total SCFA, acetate, and propionate. Additionally, the 0.5% inclusion level demonstrated the highest (p < 0.05) metabolizable energy and microbial crude protein, while the 2% level reduced these measures compared to the control. It is concluded that L. nobilis leaves can be included at 0.5% of the ruminant diet (e.g., sheep) to improve ruminal fermentation and reduce CH₄ production. Full article

(This article belongs to the Section Industrial Fermentation)

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18 pages, 2360 KB

Open AccessEditor’s ChoiceArticle

Black Tea Kombucha Consumption: Effect on Cardiometabolic Parameters and Diet Quality of Individuals with and without Obesity

by Gabriela Macedo Fraiz, Mirian A. C. Costa, Rodrigo R. Cardoso, James R. Hébert, Longgang Zhao, Viviana Corich, Alessio Giacomini, Fermín I. Milagro, Frederico A. R. Barros and Josefina Bressan

Fermentation 2024, 10(8), 384; https://doi.org/10.3390/fermentation10080384 - 26 Jul 2024

Cited by 6 | Viewed by 5551

Abstract

Background: Kombucha, a fermented tea, has been suggested as an adjuvant in the treatment of obesity. Although animal and in vitro studies indicate its promising benefits, exploring kombucha’s impact on human health is necessary. Methods: This quasi-experimental pre–post-intervention assessed the effect of black [...] Read more.

Background: Kombucha, a fermented tea, has been suggested as an adjuvant in the treatment of obesity. Although animal and in vitro studies indicate its promising benefits, exploring kombucha’s impact on human health is necessary. Methods: This quasi-experimental pre–post-intervention assessed the effect of black tea kombucha consumption on cardiometabolic parameters for 8 weeks, considering the quality of the diet of individuals with and without obesity. Diet quality was assessed through the Dietary Inflammatory Index^® and Dietary Total Antioxidant Capacity. Paired t-test/Wilcoxon was applied to compare differences between pre- and post-intervention (α = 0.05). Results: After the intervention, individuals with obesity showed a decrease in insulin, HOMA-IR, and GGT; those without obesity showed an increase in total cholesterol and alkaline phosphatase, but this was only observed in those with a worsened diet quality. Conclusion: kombucha intake demonstrated positive impacts on the metabolic health of individuals with obesity beyond the importance of combining it with healthy eating patterns. Full article

(This article belongs to the Special Issue Probiotics, Prebiotics and Their Use as Innovative Ingredients in Food Technology)

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16 pages, 5554 KB

Open AccessEditor’s ChoiceArticle

Optimizing Oxygen Exposure during Kombucha Brewing Using Air-Permeable Silicone Bags

by Briana Abigail R. Czarnecki, Kortnie M. Chamberlain, Ian M. Loscher, Emily R. Swartz, Lieke M. Black, Emma C. Oberholtzer, Jordan C. Scalia, Bret A. Watson, Lauren E. Shearer, John N. Richardson and Jeb S. Kegerreis

Fermentation 2024, 10(7), 371; https://doi.org/10.3390/fermentation10070371 - 20 Jul 2024

Cited by 2 | Viewed by 4238

Abstract

As the commercial and home brewing of kombucha expands to accommodate its increased popularity, novel brewing practices that generate non-alcoholic kombucha in an efficient manner become valuable. The research presented in this work compares kombucha brewed in a glass jar brewing vessel to [...] Read more.

As the commercial and home brewing of kombucha expands to accommodate its increased popularity, novel brewing practices that generate non-alcoholic kombucha in an efficient manner become valuable. The research presented in this work compares kombucha brewed in a glass jar brewing vessel to that brewed in an air-permeable silicone bag. Identical kombucha ferments with various sugar food sources were prepared and placed in each vessel, and variables such as titratable acidity, pH, alcohol by volume, gluconic acid concentration, acetic acid concentration, and sugar content were studied as a function of time. The results indicated that, regardless of the food source, kombucha brewed in an air-permeable bag exhibited more efficient acid production, lower ethanol concentration, and greater sugar utilization relative to equivalent kombucha brewed in a jar. Full article

(This article belongs to the Special Issue New Fermented Tea: Processing Technology, Microbiology and Health Benefits: 2nd Edition)

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17 pages, 2222 KB

Open AccessEditor’s ChoiceArticle

Phenotypic Characterization of Fermentation Performance and Stress Tolerance in Commercial Ale Yeast Strains

by Anqi Chen, Qiqi Si, Qingyun Xu, Chenwei Pan, Yuhan Cheng and Jian Chen

Fermentation 2024, 10(7), 364; https://doi.org/10.3390/fermentation10070364 - 18 Jul 2024

Viewed by 5744

Abstract

Yeast plays a crucial role in the fermentation industry, particularly in alcoholic beverage production, where robustness and metabolic flexibility are essential. This study aimed to investigate the stress tolerance and metabolic capabilities of seven commercial ale yeast strains under various stress conditions, including [...] Read more.

Yeast plays a crucial role in the fermentation industry, particularly in alcoholic beverage production, where robustness and metabolic flexibility are essential. This study aimed to investigate the stress tolerance and metabolic capabilities of seven commercial ale yeast strains under various stress conditions, including temperature, pH, osmotic pressure, glucose starvation, and ethanol concentration. Detailed growth assays and stress tolerance tests were utilized to evaluate fermentation efficiency, carbon source utilization, and stress adaptation. Significant variability was observed among the strains. ACY169 and ACY150 demonstrated high overall stress tolerance, making them suitable for high-gravity brewing and processes involving extreme temperature fluctuations. ACY10 showed robust performance under acid stress, making it ideal for sour beer production. In contrast, ACY5 exhibited limited adaptability under stress, with longer doubling times and reduced metabolic activity. The study also revealed differences in carbon source utilization, with ACY169 displaying exceptional metabolic versatility by efficiently fermenting various sugars, including glucose, fructose, maltose, and raffinose. ACY10 and ACY150 exhibited balanced fermentation profiles with high ethanol production rates, while ACY9 demonstrated the highest glucose consumption rate but lower ethanol yields and significant acidification. Full article

(This article belongs to the Special Issue Saccharomyces cerevisiae Strains and Fermentation: 2nd Edition)

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20 pages, 2733 KB

Open AccessEditor’s ChoiceArticle

A Semi-Continuous Fermentation Process for Pulque Production Using Microfiltration-Sterilized Aguamiel and Aseptic Conditions to Standardize the Overall Quality of the Beverage

by Concepción Calderón-García, Paula Cecilia Guadarrama-Mendoza, Edith Ponce-Alquicira, Adelfo Escalante, Yesica Ruiz-Ramírez and Rogelio Valadez-Blanco

Fermentation 2024, 10(7), 342; https://doi.org/10.3390/fermentation10070342 - 28 Jun 2024

Cited by 3 | Viewed by 3671

Abstract

Despite the current appreciation of pulque as a probiotic fermented beverage, pulque has been also regarded as a poor-quality product, particularly due to the lack of sanitary control during its elaboration. To address this problem, a semi-continuous fermentation system was established, emulating the [...] Read more.

Despite the current appreciation of pulque as a probiotic fermented beverage, pulque has been also regarded as a poor-quality product, particularly due to the lack of sanitary control during its elaboration. To address this problem, a semi-continuous fermentation system was established, emulating the artisanal production process. Microfiltration-sterilized aguamiel was employed as the substrate, whereas a good-quality pulque was used as the fermentation inoculum. During the fermentation, the physicochemical, microbiological (lactic acid and Leuconostoc-type bacteria and yeasts) and sensory characteristics of the must were monitored. The isolated microorganisms were identified by molecular biology and MALDI-MS techniques. The sterilization of aguamiel by microfiltration did not negatively affect its physicochemical attributes. After 6–8 days of operation of the semi-continuous bioreactor, the fermentation reached a quasi-stationary state considering most of the parameters monitored during the experiment. The final fermentation product presented similar physicochemical, microbial and sensory properties to those of the pulque inoculum. The genera identified were Leuconostoc, Lentilactobacillus, Lactobacillus, Liquorilactobacillus, Fructilactobacillus and Saccharomyces. The strains Lentilactobacillus diolivorans and Liquorilactobacillus capillatus and uvarum have not been previously isolated from pulque. In conclusion, the fermentation system developed in this work was effective to standardize the quality of pulque while preserving the positive attributes of the artisanal process, thus harnessing the probiotic properties of pulque. Full article

(This article belongs to the Section Fermentation for Food and Beverages)

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10 pages, 668 KB

Open AccessEditor’s ChoiceArticle

Evaluation of Essential Oils and Their Blends on the Fermentative Profile, Microbial Count, and Aerobic Stability of Sorghum Silage

by Elon S. Aniceto, Tadeu S. Oliveira, José R. Meirelles, Jr., Ismael N. Silva, Elvanio J. L. Mozelli Filho, Raphael S. Gomes, Juliana P. Arévalo and Patrícia R. Moraes

Fermentation 2024, 10(7), 335; https://doi.org/10.3390/fermentation10070335 - 27 Jun 2024

Cited by 4 | Viewed by 2431

Abstract

This study aims to evaluate the effect of these essential oils and their blends on the fermentative profile, losses by gases and effluents, nutritional value, microbial count, and aerobic stability of sorghum silage. A completely randomized design was used with eight treatments and [...] Read more.

This study aims to evaluate the effect of these essential oils and their blends on the fermentative profile, losses by gases and effluents, nutritional value, microbial count, and aerobic stability of sorghum silage. A completely randomized design was used with eight treatments and four repetitions. The evaluated treatments were the following: control (CON), without any essential oil; rosemary (Ros); tea tree (TT); citronella (Cit); Ros + TT (50% + 50%); Ros + Cit (50% + 50%); TT + Cit (50% + 50%); and Ros + TT + Cit (33% + 33% + 33%). A 1000 mg/kg dose of ensiled mass (as-fed basis) was used for each of the treatments. The addition of essential oils and their blends had a significant impact (p < 0.05) on the chemical composition of sorghum silage. Crude protein content increased (p < 0.001) with the use of essential oils and their blends. The Ros affected (p < 0.05) the fibrous fraction of sorghum silage. Neutral detergent fiber in vitro degradability was reduced (p = 0.003) when we used the blend TT + Cit compared to Ros and TT. We observed that only Ros did not reduce acetic acid concentration (p = 0.031) compared to the CON. The essential oils and their blends did not affect losses (p > 0.05). Lactic acid bacteria population increased (p = 0.039) when using the blend Ros + TT + Cit compared to the CON. However, the populations of entero-bacteria and fungi were not affected (p > 0.05) by the essential oils or their blends. For aerobic stability, we observed that Ros increased (p < 0.001) the air exposure time of the sorghum silage. Furthermore, the essential oils impacted the sorghum silage’s pH, which affected (p = 0.003) its aerobic stability. In conclusion, the essential oils did not reduce sorghum silage losses. However, the Ros improved the nutritional quality and aerobic stability of sorghum silage, while the blend Ros + TT + Cit increased the lactic acid bacteria count in the silage. More in-depth studies are needed to elucidate the action of essential oils as silage additives. Full article

(This article belongs to the Special Issue Application of Fermentation Technology in Animal Nutrition)

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19 pages, 3912 KB

Open AccessEditor’s ChoiceArticle

The Formulation of a Natural Detergent with a Biosurfactant Cultivated in a Low-Cost Medium for Use in Coastal Environmental Remediation

by Ivison A. da Silva, Fabíola Carolina G. de Almeida, Romulo N. Alves, Maristela C. C. Cunha, Jéssica Cristina M. de Oliveira, Mucio Luiz B. Fernandes and Leonie A. Sarubbo

Fermentation 2024, 10(7), 332; https://doi.org/10.3390/fermentation10070332 - 26 Jun 2024

Cited by 5 | Viewed by 5517

Abstract

Green surfactants have significant potential for improving environmental remediation methods. The aim of the present study was to formulate a green natural detergent containing the biosurfactant produced by Starmerella bombicola ATCC 22214 grown in 1.2% canola oil, 10% sucrose, and 0.5% corn steep [...] Read more.

Green surfactants have significant potential for improving environmental remediation methods. The aim of the present study was to formulate a green natural detergent containing the biosurfactant produced by Starmerella bombicola ATCC 22214 grown in 1.2% canola oil, 10% sucrose, and 0.5% corn steep liquor. The biosurfactant reduced surface tension to 31.84 mN/m and was produced at a yield of 22 g/L. Twelve formulations were proposed using cottonseed oil as the natural solvent and different stabilisers (vegetable wax, hydroxyethyl cellulose, and sodium alginate). The detergent was evaluated for its emulsifying capacity and stability over a 10-day period. Ecotoxicity was investigated using the marine recruitment test on metal plates covered with paint into which the biosurfactant was incorporated as well as tests with a microcrustacean and vegetable seeds. The formulation designated H, consisting of 1% biosurfactant, 40% cottonseed oil, and 2% hydroxyethyl cellulose, achieved the best results. The formulation exhibited both stability and emulsifying capacity (100% of petroleum). The ecotoxicity tests revealed the safety of the natural detergent. The detergent achieved satisfactory oil dispersion and solubilised 98% of the oil impregnated on the rock. The results indicate that the natural detergent holds promise for efficiently cleaning up environmental areas contaminated with oil and petroleum products. Full article

(This article belongs to the Special Issue Use of Agro-Industrial Waste and By-Products for the Sustainable Production of Eco-Friendly Surface-Active Compounds)

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12 pages, 1628 KB

Open AccessEditor’s ChoiceArticle

Antioxidant and Anticancer Potential of Extracellular Polysaccharide from Porphyridium aerugineum (Rhodophyta)

by Juliana G. Ivanova, Tanya S. Toshkova-Yotova, Reneta A. Toshkova, Veronika R. Deleva, Ani K. Georgieva and Liliana G. Gigova

Fermentation 2024, 10(5), 259; https://doi.org/10.3390/fermentation10050259 - 15 May 2024

Cited by 8 | Viewed by 3402

Abstract

Porphyridium aerugineum is a unicellular freshwater red microalga that synthesizes and secretes into the culture medium an extracellular polysaccharide (EPS). In this study, algal growth and polysaccharide production, as well as the antioxidant capacity and antitumor effect of Porphyridium aerugineum EPS (PaEPS), were [...] Read more.

Porphyridium aerugineum is a unicellular freshwater red microalga that synthesizes and secretes into the culture medium an extracellular polysaccharide (EPS). In this study, algal growth and polysaccharide production, as well as the antioxidant capacity and antitumor effect of Porphyridium aerugineum EPS (PaEPS), were investigated. Cultivation of the microalgae was carried out in a photobioreactor under controlled conditions. Algal growth and the amount of EPS were monitored daily. The accumulated polysaccharide was extracted and lyophilized. At the end of cultivation, the concentration of microalgal biomass and PaEPS reached 3.3 and 1.2 g L⁻¹, respectively. To examine the antioxidant capacity of PaEPS, FRAP and ABTS assays were performed. The cytotoxic activity of PaEPS was evaluated on the tumor cell lines MCF-7 (breast cancer) and HeLa (cervical adenocarcinoma) and on BJ (a non-tumor human skin fibroblast cell line), using MTT assay. The results obtained indicated that P. aerugineum polysaccharide exhibited a high ABTS radical-scavenging activity reaching up to 55%. The cytotoxic effect was best expressed in MCF-7 cells treated for 72 h with 1000 µg/mL PaEPS, where tumor cell proliferation was inhibited by more than 70%. Importantly, the PaEPS treatments did not significantly affect the viability of BJ cells. These findings promote the biotechnological production of P. aerugineum extracellular polysaccharide and reveal its potential as an anticancer and antioxidant agent for future applications. Full article

(This article belongs to the Special Issue Cyanobacteria and Eukaryotic Microalgae)

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15 pages, 831 KB

Open AccessEditor’s ChoiceArticle

Transcriptome Analysis of Sake Yeast in Co-Culture with kuratsuki Kocuria

by Karin Kobayashi and Hiromi Nishida

Fermentation 2024, 10(5), 249; https://doi.org/10.3390/fermentation10050249 - 10 May 2024

Cited by 2 | Viewed by 2647

Abstract

Kuratsuki bacteria enter the sake production process and affect the flavor and taste of sake. This study compared gene expression in the sake yeast Saccharomyces cerevisiae in co-culture with kuratsuki Kocuria to that in monoculture. Among the 5922 genes of S. cerevisiae, [...] Read more.

Kuratsuki bacteria enter the sake production process and affect the flavor and taste of sake. This study compared gene expression in the sake yeast Saccharomyces cerevisiae in co-culture with kuratsuki Kocuria to that in monoculture. Among the 5922 genes of S. cerevisiae, 71 genes were upregulated more than 2-fold, and 61 genes were downregulated less than 0.5-fold in co-culture with kuratsuki Kocuria. Among the stress-induced genes, fourteen were upregulated, and six were downregulated. Among the fourteen upregulated genes, six were induced in response to replication stress. Although the G1 cyclin gene CLN3 was upregulated by more than 2-fold, eight genes that were induced in response to meiosis and/or sporulation were also upregulated. Fourteen metabolism-related genes, for example, the glyceraldehyde-3-phosphate dehydrogenase genes TDH1, TDH2, and TDH3, were downregulated by less than 0.5-fold in co-culture with kuratsuki Kocuria. The gene expression patterns of S. cerevisiae co-cultured with kuratsuki Kocuria differed from those co-cultured with lactic acid bacteria. Therefore, S. cerevisiae responded differently to different bacterial species. This strongly suggests that kuratsuki bacteria affect gene expression in sake yeast, thereby affecting the flavor and taste of sake. Full article

(This article belongs to the Special Issue Applied and Fundamental Studies of Yeast in Fermented Foods and Beverages)

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24 pages, 2065 KB

Open AccessEditor’s ChoiceArticle

Autochthonous Ingredients for Craft Beer Production

by Vanesa Postigo, Luz Mauro, Teresa Diaz, Roberto Saiz, Teresa Arroyo and Margarita García

Fermentation 2024, 10(5), 225; https://doi.org/10.3390/fermentation10050225 - 24 Apr 2024

Cited by 6 | Viewed by 3723

Abstract

Innovation in the beer market focuses on research into the different ingredients that make up this popular and sought-after beverage. Some of these innovations have focused on the use of autochthonous ingredients, which bring added value to products, reduce production costs and environmental [...] Read more.

Innovation in the beer market focuses on research into the different ingredients that make up this popular and sought-after beverage. Some of these innovations have focused on the use of autochthonous ingredients, which bring added value to products, reduce production costs and environmental impact, and provide beers with special organoleptic characteristics. This study focuses on the use of autochthonous ingredients from the Community of Madrid and the design of four recipes that are suited to these ingredients and consumer demand. In terms of the ingredients used, the micromalting of barley grown in the CM was carried out, while hops (Cascade variety for bittering hops and wild hops Rayo verde Tajuña and Torreta Tajuña for aroma) and yeast strains (Saccharomyces cerevisiae G 520 and G 354) were selected from previous studies, which were also sourced from the CM. For the barley malt, parameters such as protein content were determined, which was at the maximum limit but did not affect the final quality of the beers. The content of α- and β-acids in the hops was also determined, being higher in the Cascade variety. Different physicochemical analyses (GC, aromatic compounds, bitterness, colour, SO₂, polyphenols, and antioxidant capacity) were carried out to determine the quality of the beers obtained from the four recipes designed, as well as tastings by a panel of experts and consumers. Finally, two recipes were rated the best by a panel of experts and consumers, where the cereal, hop, and fruit flavours stood out for their aromatic profile. Full article

(This article belongs to the Special Issue Advances in Beverages, Food, Yeast and Brewing Research, 3rd Edition)

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20 pages, 3098 KB

Open AccessEditor’s ChoiceArticle

Photoautotrophic Production of Docosahexaenoic Acid- and Eicosapentaenoic Acid-Enriched Biomass by Co-Culturing Golden-Brown and Green Microalgae

by Anna-Lena Thurn, Josef Schobel and Dirk Weuster-Botz

Fermentation 2024, 10(4), 220; https://doi.org/10.3390/fermentation10040220 - 18 Apr 2024

Cited by 10 | Viewed by 3208

Abstract

Marine microalgae offer a sustainable alternative source for the human diet’s essential omega-3-fatty acids, including docosahexaenoic acid (DHA, C22:6) and eicosapentaenoic acid (EPA, C20:5). However, none of them can produce DHA and EPA in a nutritionally balanced ratio of 1:1. As shown recently, [...] Read more.

Marine microalgae offer a sustainable alternative source for the human diet’s essential omega-3-fatty acids, including docosahexaenoic acid (DHA, C22:6) and eicosapentaenoic acid (EPA, C20:5). However, none of them can produce DHA and EPA in a nutritionally balanced ratio of 1:1. As shown recently, the phototrophic co-cultivation of the golden-brown microalgae Tisochrysis lutea (DHA producer) with the green microalgae Microchloropsis salina (EPA producer) can provide microalgae biomass with a balanced DHA-to-EPA ratio with increased productivity compared to monocultures. This study evaluates whether other golden-brown (Isochrysis galbana) and green microalgae (Nannochloropsis oceanica, Microchloropsis gaditana) can enable the phototrophic batch production of omega-3 fatty acids in a nutritionally balanced ratio in co-culture. All co-cultivations applying a physically dynamic climate simulation of a repeated sunny summer day in Australia in LED-illuminated flat-plate gas lift photobioreactors resulted in increased biomass concentrations compared to their respective monocultures, achieving balanced DHA-to-EPA ratios of almost 1:1. Using urea instead of nitrate as a nitrogen source increased the EPA content by up to 80% in all co-cultures. Light spectra measurements on the light-adverted side of the photobioreactor showed that increased biomass concentrations in co-cultures could have been related to enhanced light use due to the utilization of different wavelengths of the two microalgae strains, especially with the use of green light (500–580 nm) primarily by golden-brown microalgae (I. galbana) and orange light (600–620 nm) predominantly used by green microalgae (N. oceanica). Phototrophic co-cultivation processes thus promise higher areal biomass yields if microalgae are combined with complimentary light-harvesting features. Full article

(This article belongs to the Special Issue The Future of Fermentation Technology in the Biorefining Process: 2nd Edition)

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13 pages, 5694 KB

Open AccessEditor’s ChoiceArticle

Biohydrogen, Volatile Fatty Acids, and Biomethane from Mezcal Vinasses—A Dark Fermentation Process Evaluation

by Sergio A. Díaz-Barajas, Iván Moreno-Andrade, Edson B. Estrada-Arriaga, Liliana García-Sánchez and Marco A. Garzón-Zúñiga

Fermentation 2024, 10(4), 217; https://doi.org/10.3390/fermentation10040217 - 16 Apr 2024

Cited by 2 | Viewed by 2710

Abstract

Mezcal is a drink made in Mexico, the production of which generates vinasses with a high content of organic matter (OM) that is not utilized. However, these residues have the potential to be drawn upon in dark fermentation (DF) processes to obtain biogas [...] Read more.

Mezcal is a drink made in Mexico, the production of which generates vinasses with a high content of organic matter (OM) that is not utilized. However, these residues have the potential to be drawn upon in dark fermentation (DF) processes to obtain biogas rich in biohydrogen, biomethane, and volatile fatty acids (VFAs) with the potential to become biofuels. In the present work, the effect of reaction time (RT) and organic load (OL) was assessed based on the efficiency of removing OM, the production of VFAs, and the generation and composition of biogas in a process of DF fed with mezcal vinasses. The results show that increasing the RT and decreasing the OL increases COD removal but decreases biohydrogen production. The maximum production of H₂ (64 ± 21 NmL H₂/L_reactor) was obtained with the lowest RT (1 d) and the highest OL (13.5 gCODm³d⁻¹), while the highest accumulation of VFAs (2007 ± 327 mg VFA/L) was obtained with an RT of 3 d. It was determined that RT and OL are key parameters in DF processes for biohydrogen and VFA production. Full article

(This article belongs to the Special Issue Fermentative Biohydrogen Production)

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16 pages, 5217 KB

Open AccessEditor’s ChoiceArticle

Ethanol Production from a Mixture of Waste Tissue Paper and Food Waste through Saccharification and Mixed-Culture Fermentation

by Hongzhi Ma, Yueyao Wang, Pin Lv, Jun Zhou, Ming Gao, Dayi Qian, Bo Song and Qunhui Wang

Fermentation 2024, 10(4), 194; https://doi.org/10.3390/fermentation10040194 - 2 Apr 2024

Cited by 5 | Viewed by 3902

Abstract

This study focused on the co-fermentation of food waste and tissue paper to produce ethanol, which will eliminate the need for additional nitrogen sources and nutrients, thereby reducing production costs. In response to the inhibitory effect of the high concentrations of glucose present [...] Read more.

This study focused on the co-fermentation of food waste and tissue paper to produce ethanol, which will eliminate the need for additional nitrogen sources and nutrients, thereby reducing production costs. In response to the inhibitory effect of the high concentrations of glucose present in mixed-substrate hydrolysates on xylose fermentation, a co-fermentation process using Saccharomyces cerevisiae and Candida shehatae was proposed. This approach reduced the fermentation time by 24 h, increased the xylose utilization rate to 88%, and improved the ethanol yield from 41% to 46.5%. The impact of external conditions and corresponding optimization were also analyzed in this process. The optimum conditions were a 1:3 ratio of Saccharomyces cerevisiae to Candida shehatae, a pH of 5, and shaking at 150 r/min, and by employing dynamic temperature control, the ethanol production was increased to 21.98 g/L. Compared to conventional processes that only use Saccharomyces cerevisiae, this method enhanced the ethanol yield from 41% to 49%. Full article

(This article belongs to the Special Issue Anaerobic Digestion: Waste to Energy)

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