Search Results (36)

Although beer fermentation has traditionally been carried out with Saccharomyces, the boom in craft brewing has led to the use of non-conventional yeast species for beer production. This group also includes non-Saccharomyces starters, which are commonly used in winemaking and which have different technological characteristics compared to standard representatives of the Saccharomyces genus. One of the important characteristics of the non-Saccharomyces group is the richer enzyme profile, which leads to the production of beverages with different taste and aroma profiles. The aim of this study was to investigate sweet and hopped wort fermentation with seven strains of active dry non-conventional yeasts of Lachancea spp., Metschnikowia spp., Torulaspora spp. and a mixed culture of Saccharomyces cerevisiae and Torulaspora delbrueckii. One ale and one lager active dry yeast strain were used as control strains. The extract consumption, ethanol production, degree of fermentation, pH drop, as well as the yeast secondary metabolites formed by the yeast (higher alcohols, esters and aldehydes) in sweet and hopped wort were investigated. The results indicated that all of the studied types of non-conventional yeasts have serious potential for use in beer production in order to obtain new beer styles. For the purposes of this study, statistical methods, principle component analysis (PCA) and correlation analysis were used, thus establishing the difference in the fermentation kinetics of the growth in the studied species in sweet and hopped wort. It was found that hopping had a significant influence on the fermentation kinetics of some of the species, which was probably due to the inhibitory effect of the iso-alpha-acids of hops. Directions for future research with the studied yeast species in beer production are presented. Full article

Pulsed electric field (PEF) and high-pressure processing (HPP) are non-thermal treatments, developed to ensure preservation of food products whilst maintaining taste and valuable nutrients. In this study, we investigated their potential for the inactivation of 3 commercial exogenous pectinases (polygalacturonase, pectin transeliminase, pectin esterase) commonly used in juice processing for clarification of juices. The inactivation of these enzymes after processing is mandatory by European law. Clear apple juice was treated with both non-thermal processing methods, as well as with thermal pasteurization as the standard method. For HPP, 3 pressures (250, 450, and 600 MPa) and different holding times (from 2 to 12 min) were tested. For PEF, 3 electric field intensities (10, 13, and 15 kV/cm) and different specific energy values (from 121 to 417 kJ/kg). Standard thermal pasteurization resulted in a complete inactivation of all tested pectinases. HPP treatment only showed marginal effects on polygalacturonase and pectin transeliminase at the highest pressure and holding times, which are beyond levels used in industrial settings. For PEF, dependence upon high electric field strength and specific energy values was evident; however, here too, the effect was only moderate at the levels attainable within the scope of this study. Assuming a continued linear relationship, usable results could be achieved in an industrial setting, albeit under more extreme conditions. Full article

This study employed shotgun metagenomics to investigate microbial dynamics, phage-bacteria interactions, and functional genes throughout a three-month apple vinegar fermentation process. A total of 5621 microbial species were identified, revealing three distinct phases: (i) Enterobacteria and non-Saccharomyces species dominated the initial substrate; (ii) S. cerevisiae and Leuconostoc pseudomesenteroides prevailed in the intermediate phase; and (iii) acetic acid bacteria (Acetobacter ghanesis and Gluconobacter spp.), alongside non-Saccharomyces species (Pichia kudriavzevii and Malassezia restricta), dominated the final stages. Bacteriophage analysis revealed the presence of phages targeting spoilage bacteria, such as Pseudomonas and Erwinia, suggesting a role in regulating microbial stability and enhancing fermentation control. Functional metagenomic analysis highlighted key pathways associated with microbial growth and metabolite production, including carbohydrate and amino acid metabolism, energy production, and glycan biosynthesis. Enzymes involved in stress adaptation and secondary metabolism, including oxidative phosphorylation and phenolic compound synthesis, demonstrated microbial resilience and their potential role in shaping the product’s sensory and functional properties. Moreover, Enterobacteriaceae species were associated with pectin degradation during the early stages, aiding substrate breakdown. These findings are crucial for microbial and phage management in fermentation technology, offering valuable insights for innovation in the vinegar industry. Full article

This study examined the ability of four beneficial strains (Lactobacillus rhamnosus LbRE-LSAS, Bifidobacterium animalis subsp. lactis Bb12, and two yogurt starters TA040 and LB340) to ferment MRS or milk containing free linoleic acid (0, 0.5, or 1 mg/mL). The goal was to produce an enriched conjugated linoleic acid (CLA) isomers’ yogurt-type beverage. Linoleic acid (LA) at 0.5 mg/mL did not interfere with the growth of the assayed bacteria on de Man Rogosa and Sharpe broth (MRS) or milk. On the other hand, increasing the content of LA in the MRS or yogurt-type beverage to 1 mg/mL slightly inhibited all strains and prevented accumulating high biomasses. A gas chromatography analysis of the fatty acid profiles confirmed the bioconversion of LA. The yogurt starters TA040 and LB340 had the highest bioconversion rates in the yogurt-type beverages, whereas the probiotic Bb12 strain was the most interesting at converting LA into its active CLA. CLA from the MRS supernatants of TA040, Bb12, and LbRE-LSAS had maximum antibacterial activities against S. typhimurium, E. coli, and S. aureus, respectively. Whey from the Bb12 beverage showed an inhibitory effect against all pathogens. These results suggest that all strains could be used as starter cultures in the proposition of a yogurt-type beverage with a high CLA content and antibacterial potential. Full article

The cashew apple constitutes approximately 90% of the total fruit mass produced by the cashew tree, with the remaining 10% being the cashew nut. Despite its high nutritional value, it is regarded as an agricultural byproduct. Numerous scientific studies have explored the technological and nutritional potential of the cashew apple by leveraging microorganisms in its fermentation process for beverage applications. This paper provides an overview of existing fermented cashew apple beverages and discusses perspectives for new fermented cashew apple products. Five fermented cashew apple beverages were recorded. These include wine, edible alcohol, probiotic and prebiotic beverages, and cashew apple-based vinegar. New fermented cashew apple beverages with organoleptic, nutritional, and functional properties can be considered. Among these are fermented cashew apple beverages such as kefir or kombucha-type drinks. A promising avenue for future research is the exploration of the indigenous microbiota of the cashew apple and their interactions within a consortium. This could lead to innovative developments in food technology and improvements in the organoleptic and nutritional characteristics of fermented cashew apple beverages. Full article

Teas derived from Camellia sinensis are traditionally used in kombucha fermentation, a process in which bacteria and yeasts play key roles. This study aimed to evaluate the effects of green, black, and white teas, as well as their combinations, on the physicochemical properties, antioxidant capacity, and total phenolic compound content of kombucha. In addition, the production of kombucha flavored with fruits. Statistical analysis of simplex centroid mixture design indicated that green tea promoted a positive increase in total phenolic content and antioxidant activities against ABTS and DPPH free radicals, being observed at 5868.46 µmol/mL, 705.40 µmol/mL, and 380.77 mg GAE/100 mL in the kombucha prepared using this tea individually. Then, six kombucha beverages were prepared from green tea, flavored with grape, caja, cashew apple, genipap, passion fruit, and tamarind. The phenolic profile analysis revealed the presence of twenty-six compounds, including twenty-five phenolics and one caffeine derivative. Among the beverages, tamarind-flavored kombucha stood out, exhibiting the highest total flavonoid content (156.77 mg EQ/g), which highlights the positive influence of tamarind on the bioactive properties of kombucha beverages. These results provide valuable insights to optimize kombucha production and explore the potential beneficial effects of flavored non-alcoholic beverages. Full article

The objective of this study was to investigate the impact of co-fermentation of Italia and Negra Criolla grape musts using non-Saccharomyces yeast strains (NSYSs) isolated from both grape varieties, on the major volatile compounds and sensory characteristics of Piscos (distilled spirits). Native NSYSs previously isolated from Italia (Pichia terricola, Metschnikowia pulcherrima, and Naganishia vaughanmartiniae) and Negra Criolla (Vishniacozyma carnescens, Vishniacozyma heimaeyensis, and Aureobasidium pullulans) grapes’ skins were inoculated at the beginning of grape must fermentation. A centroid simplex design was applied in order to obtain 10 representative yeast blends for use as mono- (n = 3), bi- (n = 3), and ternary (n = 4) inoculations. Additionally, a control sample without inoculum was also set up. For each yeast blend, the volatile composition and sensory characteristics of Piscos were evaluated. Results showed that mono-inoculation using specific NSYSs, such as P. terricola, M. pulcherrima, and N. vaughanmartiniae, led to a notable predominance of some terpenes such as α-terpineol, citronerol, and geraniol in Pisco from Italia grapes compared to the control Pisco. Conversely, in Pisco from Negra Criolla grapes, where V. carnescens, V. heimaeyensis, and A. pullulans were used in a similar mono-inoculation process, a higher presence of phenylethyl alcohol and 2-phenylethyl acetate compared to the control was observed. The sensory analysis revealed that citrus, floral, alcohol, and syrup descriptors had a higher intensity in mono-inoculated Pisco Italia, whereas spice, herbaceous, and cooked vegetable descriptors had the highest intensity in Negra Criolla Piscos produced with ternary NSYS inoculum inoculations. This study demonstrates that the use of native non-Saccharomyces yeast strains in the co-fermentation of grape musts can significantly influence the volatile profile and sensory characteristics of Pisco. These findings will allow us to establish new inoculation strategies to impact the overall sensory and aromatic profile of the Piscos produced with different grape varieties. Full article

Background: The role of the S. cerevisiae strain in defining the volatile fingerprint is expressed throughout alcoholic fermentation and post-fermentation sur lie aging and is crucial for customizing the wine style. Methods: In this study, the alcoholic fermentation was carried out in a synthetic must to exclusively bring out the performance of the yeast in terms of volatile compound production, excluding the effect of the grape. Results: Among the 33 volatile organic compounds identified in the synthetic wines by GC-MS, esters, alcohols, and acids, represented the major groups for the nine different commercial oenological strains tested. All the relevant differences in the volatile fingerprint of the synthetic wines, which were lab-scale fermented, were quantitative rather than qualitative. The clustergram representation of the volatiles revealed an outstanding fingerprint for two strains (VIN13 and VIN7) among those tested, featuring hexanoic acid, octanoic acid, the corresponding esters (ethyl hexanoate, ethyl octanoate), and the acetates (2-phenylethyl acetate, isoamyl acetate), all at the highest levels. No relationship was appreciated between the fermentation rate and the volatile fingerprints. Conclusions: The outcomes of this study address the wine industry’s needs, supplying a full characterization of a broad range of commercial yeasts’ ability in fermentative volatile production. Full article

The demand for functional beverages with clean labels is growing. Arthrospira platensis and fermented products offer bioactive compounds, including antimicrobials. This study aimed to produce food-grade extracts from lactic acid-fermented A. platensis and evaluate its antimicrobial activity, lipid-reducing and glucose uptake effects, and antioxidant properties. An in situ test was also conducted to assess antimicrobial activity in commercial soft drinks against Escherichia coli. Arthrospira platensis was fermented with five different QPS LAB strains: Limosilactobacillus fermentum UPCCO 1986, Companilactobacillus farciminis UPCCO 4841, Levilactobacillus brevis UPCCO 4873, Lentilactobacillus diolivorans UPCCO 5571, and Latilactobacillus curvatus UPCCO 6133, obtaining good results in aerobic and anaerobic conditions. The results have shown that the most versatile strain in fermenting biomass is L. brevis UPCCO 4873. Important in vitro antimicrobial activity was seen against Salmonella enterica, Listeria monocytogenes, Staphylococcus aureus and Escherichia coli. The extracts that exerted the highest antimicrobial activity (4841AE/AN, 5571AE, and 6133AN) were assessed for the in situ antimicrobial activity against E. coli ATCC 11229. Overall, the antimicrobial activity of the extracts was concentration-dependent, with higher concentrations exhibiting bactericidal effects and lower concentrations displaying bacteriostatic effects. Extracts from fermented A. platensis have also significantly reduced the neutral lipid reservoirs, which were not observed without fermentations. The strongest lipid-reducing effect was obtained with A. platensis fermented with Levilactobacillus brevis UPCCO 4873. This work opens the possibility of developing bioactive extracts or natural preservatives from fermented microalgae to be used in novel functional beverages. Full article

Chitosan is used as an antimicrobial agent in different agri-food applications; in winemaking, the use of chitosan from Aspergillus niger is authorized, but other sources of chitin, and consequently of chitosan, are available, such as crustaceans and insects. This work investigates the antimicrobial efficiency of chitosan from crustaceans and insects (Hermetia illucens) against non-Saccharomyces yeasts in wine. For this aim, the first step was to evaluate the effect of crustacean chitosan, tested both alone and in combination with low sulphur dioxide (SO₂) concentrations, on the cell viability of 20 non-Saccharomyces strains in the first step of fermentations inoculated with each strain. Furthermore, the strain resistance to crustacean- and insect-based chitosan was evaluated in agarized media, together with the addition of different antimicrobial concentrations. Finally, the efficiency of different antimicrobial treatments was evaluated during laboratory-scale fermentations inoculated with a selected S. cerevisiae strain. The tested strains exhibited medium/high resistance to the chitosan; in some cases, the behaviour varied in the function of species/strain, and only four strains exhibited different resistance levels, depending on the chitosan source. The addition of chitosan alone during fermentation inoculated with S. cerevisiae showed lower antimicrobial activity than SO₂, but the combined use with SO₂ showed a better effect than chitosan alone. The evaluation of the suitability of chitosan obtained from a sustainable source, such as insects, will allow us to give new information on the future applications of this natural compound for the production of wine with low sulphite content. Full article

This study aimed to evaluate the fermentative capacity of the strain Limosilactobacillus fermentum J24 in a dairy beverage with papaya puree obtained through the flash vacuum expansion (FVE) process. Changes in phenolic content and antioxidant capacity during fermentation were investigated. Results showed that the dairy beverage with the control puree exhibited higher microbial growth than the FVE puree. Phenolic content increased during fermentation in both formulations. However, the antioxidant capacity was higher in the dairy beverage with control puree. A Pearson correlation analysis revealed a strong positive correlation between microbial load and antioxidant properties in the dairy beverage with control puree. In conclusion, the control puree promoted a higher growth of Limosilactobacillus fermentum J24 and better antioxidant properties in the papaya dairy beverage. These findings lay the groundwork for developing a potential functional dairy beverage based on papaya, effectively utilizing the fruit, reducing pollution, and adding value. This study also opens avenues for further research and development in functional dairy beverages, particularly those incorporating fruit-based ingredients. Full article

Chocolate-flavored milk contributes to excessive intake of added sugars among children and adolescents, which why it is a good candidate product for sucrose replacement. This study investigates how replacing sucrose partially or completely with different sweetener systems affects the sensory profile and consumer liking. Five chocolate-flavored milk treatments were formulated, varying in sucrose replacement level (partial: 58%; complete: 100%) and sweetener system (synthetic: acesulfame-K; natural: rebaudioside M-erythritol blend). Relative-to-Reference Scaling by a trained panel confirmed that no significant differences in the sensory profile when partial sucrose replacement was compared to sucrose, whereas the complete replacement increased bitter taste, pungent flavor, licorice flavor and mouth-drying. A total of 104 consumers evaluated the treatments for liking and indicated their temporal perceptions with temporal check-all-that-apply. Latent variable clustering performed on liking ratings revealed two clusters, which perceived temporal sensory characteristics differently depending on the sweetener system. Cluster 1 preferred the sucrose control over treatments with complete and partial replacement using a natural sweetener system, with complete replacement being perceived as having off-flavor. Cluster 2 preferred the sucrose control over partial and complete replacement using either of the sweetener replacements investigated, which were characterized as off-flavored and bitter. Understanding these consumer segments enables the food industry to develop effective low-energy formulations using synthetic and natural non-nutritive sweeteners, leading to reduced sugar consumption. Full article

The exploration of space is becoming more feasible, and with this comes the possibility of performing fermentations in microgravity. Our study explores the potential effects of microgravity on a standard brewing model fermentation. As the fermentation of barley wort has been studied for centuries, there is an established foundation of knowledge with which to compare any changes that occur under microgravity. A modified ASBC miniature fermentation protocol (Yeast-14) was conducted within a Yuri 2.0 microgravity chamber to examine the response of Saccharomyces pastorianus to simulated microgravity conditions. Our findings reveal that yeast exhibited accelerated growth rates under microgravity compared to standard conditions. Additionally, the microgravity environment led to significantly lower levels of volatile compounds such as isoamyl acetate and 2-phenethyl acetate in the final product. Further genetic analysis showed significant downregulation of the ATF2 gene in the control group, potentially the mechanism behind the observed decrease in volatile compounds. These results show that while fermentation under microgravity is likely to eventually be commonplace, there may be changes in rate and gene expression that are beneficial or detrimental to the final product depending upon the desired characteristics. Full article

Berries and their products can enhance the antioxidant profile, color, and sensory characteristics of beverages, resulting in competitive, value-added products. However, a complete overview of how fermentation affects these compounds is lacking. The American black elderberry, Sambucus canadensis, is an excellent candidate for studying how berry juices are affected during fermentation due to high concentrations of color compounds, anthocyanins, and volatile compounds. Gravity, pH, titratable acidity, total anthocyanins, color, and GC-MS analyses were performed on two varieties of elderberries to examine the physical and chemical qualities of elderberry juice before and after wine fermentation. A commercial product with elderberry adjuncts added post fermentation was also analyzed. The concentration of anthocyanins degraded by ~40% as the color of the elderberry wine shifted from blue to red after fermentation. Products that added elderberries post fermentation did not see the same degradation, however, also did not incorporate the same changes to volatile compounds as observed in the fermented wine. The fermentation industry can use this study’s findings to decide how best to use fruits to improve commercial products. Full article

The use of wine dealcoholisation has multiplied in recent years as a result of various factors, including the increase in alcohol content due to global warming and changes in consumer drinking habits. There are several post-fermentation dealcoholisation methods in the literature which allow for the partial or total elimination of the alcohol content of wine. However, there are no studies on the patented very low temperature vacuum wine distillation technology called GoLo. Therefore, for the first time, this paper evaluates the quality of dealcoholised white, rose and red wines using GoLo technology. For this purpose, alcohol content, pH, total SO₂, free SO₂, total acidity and volatile acidity were measured. There were no significant differences in the variations in pH, total acidity and volatile acidity after the dealcoholisation process using GoLo technology and dealcoholised wines showed a reduction of 22.1% in total SO₂ and a complete absence of ethanol and free SO₂. A model for predicting the total SO₂ content of dealcoholised wines and a model for predicting the amount of sulphites to be added after dealcoholisation were found after the statistical treatment of the data. GoLo dealcoholisation delivers 100% removal of alcohol and free SO₂ in less time, with less loss and energy than other dealcoholisation technologies. The verification and extension of these results will be the focus of future studies. Full article