Search Results (60)

Calcium microcapsules were developed by spray-drying using mannoproteins (MPs) extracted from brewer’s spent yeast, xanthan gum (XG), and maltodextrin as encapsulating materials. The formulas included 11 g of calcium, 24 g of MP, and 0, 2, 4, or 8 g of XG 100 g⁻¹ solids, obtaining C1, C2, C3, and C4 microcapsules, respectively. Maltodextrin was added to complete 100 g of solids. Calcium intestinal (IB), colonic (CB), and total bioaccessibility (TB) were estimated after a simulated gastrointestinal digestion followed by in vitro colonic fermentation. The macromolecules of microcapsules interacted by ionic and hydrophobic forces. Microcapsules C1 and C2 showed a spherical shape. However, the addition of XG to the formulation contributed to the formation of concavities in the microcapsules. All microcapsules had higher IB than the control (CaCl₂), probably due to the calcium-chelating peptides dialyzed from MP. Moreover, C1 and C2 showed the highest IB values (≈23%). However, C3 and C4 showed the highest CB values (≈11%), attributing this effect to the short-chain fatty acids produced during colonic fermentation. Finally, C1 and C2 showed the highest TB (31.8 ± 0.1 and 32.0 ± 0.4%, respectively). The use of MP allowed for obtaining a supplement with high calcium bioaccessibility. Full article

The increasing demand for sustainable poultry production has urged the exploration of alternative feed strategies supporting animal performance and environmental goals. The first section outlines the protein requirements in broiler nutrition (19–25% crude protein) and the physiological importance of balanced amino acid profiles. Vegetal conventional protein sources are discussed in terms of their nutritional value (12.7–20.1 MJ/kg), limitations (antinutritional factors), and availability. Emerging trends in broiler nutrition highlight the integration of supplements and the need for innovative feed solutions as support for the improvement in broiler body weight and feed efficiency increase. Microbial protein sources: yeast biomass (41–60% of 100 g dry weight), microbial mixed cultures (32–76% of 100 g dry weight), and beer by-products, such as brewer’s spent yeast (43–52% of 100 g dry weight), offer promising nutritional profiles, rich in bioactive compounds (vitamin B complex, minerals, enzymes, and antioxidants), and may contribute to improved gut health, immunity, and feed efficiency when used as dietary supplements. The review also addresses the regulatory and safety considerations associated with the use of microbial protein in animal feed, emphasizing EU legislation and standards. Finally, recent findings on the impact of microbial protein supplementation on broiler growth performance, carcass traits, and overall health status are discussed. This review supports the inclusion of microbial protein sources as valuable co-nutrients that complement conventional feed proteins, contributing to more resilient and sustainable broiler production and broiler meat products. Full article

Brewer’s spent grain (BSG), the most abundant by-product from breweries, is mainly discarded or used as animal feed. However, to increase the brewing sustainability, biotechnological utilization of BSG is a much preferred solution. This study examined the fermentation of BSG, composed of old wheat bread and barley malt, by metabolic activity of Saccharomyces cerevisiae on both hydrolyzed and non-hydrolyzed media. Enzymatic hydrolysis with Viscozyme^® W FG for 6 h was selected as the most effective and was used in the further research step to prepare the hydrolyzed BSG-based medium. Both media supported almost uniform yeast growth (numbers of S. cerevisiae cells was about 8 log₁₀ CFU/g) in an acidic environment (pH value was about 5), but fermentation of hydrolyzed BSG resulted in 20% higher sugar consumption and 10% higher total titratable acidity. These findings underscore the potential of enzymatic pretreatment to improve fermentation performance. The adaptability of S. cerevisiae and the fermentability of both substrates suggest promising potential for scalable BSG valorization strategies in circular food systems. Full article

Incorporating vitamin D3 (cholecalciferol) into food is hampered by its high instability and low water solubility. Due to porous structure that favors absorption and carrying of micronutrients, brewer’s spent yeast (BSY) is an economically and technically attractive alternative to overcome the shortcomings of vitamin D3 incorporation. Using heat and shear-sensitive ingredients and additives in formulations remains challenging due to the high-temperature and shear conditions during industrial processes, such as extrusion. This study aimed to produce an extruded plant-based meat product enriched with cholecalciferol. Vitamin D3, free and impregnated in BSY (BSY-VitD3), was blended with pea protein and subjected to cooking extrusion. Product features were analyzed for color, texture, moisture, water activity, absorption capacity, and vitamin retention. Adding BSY-VitD3 reduced all texture profile parameters and altered colors. Furthermore, free VitD3 enhanced extruded water and oil absorption capacity. After extrusion, vitamin retention percentages in the products were 45.4 and 91.6%, for free and BSY-VitD3, respectively. After 1-month storage of the extruded products, vitamin retention was 38.9 and 85.1% for free and BSY-VitD3 samples, respectively. Blending vitamin D3 with BSY is a simple, fast, and effective process to facilitate incorporation of the vitamin in the formulation and protect it during cooking extrusion. Full article

Brewer’s spent yeast (BSY), a significant brewing by-product, poses environmental challenges and opportunities for valorization as a sustainable protein source. This study focuses on transforming BSY into high-value functional ingredients for food applications. A green, sustainable, and scalable process was developed to extract bioactive compounds from BSY at both laboratory and pilot scales, yielding peptide-rich fractions with robust antioxidant properties. These extracts were incorporated into prototype formulations, including protein-enriched crackers, demonstrating their potential as natural, nutritious ingredients. Physicochemical, compositional, and functional characterizations validated their application viability. The antioxidant potential of BSY fractions was confirmed through total phenolic compounds and ABTS and oxygen radical absorbance capacity assays, where the retentate from the 10 kDa ultrafiltration fraction on the pilot scale exhibited superior bioactivity, supporting its selection as the most suitable fraction for food formulations. Additionally, the transition from laboratory to pilot scale revealed slight variations in protein retention and bioactive compound recovery, emphasizing the need for process optimization. These findings highlight BSY’s potential to support circular economy practices by reducing waste while enhancing the nutritional and functional value of food products. Full article

This study evaluated the use of brewer’s spent yeast (BSY) as an adsorbent for tannins from a chestnut shell extract (CS tannin extract). This extract was derived from an alkaline treatment (5% NaOH (v/v)) to recover cellulosic material from chestnut shells and needed valorization. Various BSY treatments, including lyophilization, immobilization in calcium alginate beads, and alkaline and acid treatments, were tested to identify which had the best tannin adsorption capacity. The results highlight BSY’s potential as a system to valorize tannins from this treatment solution. Full article

This study investigates the potential of additive-free extraction techniques to produce a proteolytically active yeast extract for use in the food industry. Brewer’s spent yeast, a by-product of the brewing industry, is utilized as a feedstock, and thus a new route for its valorization is proposed. Four methods of releasing these components while maintaining their intrinsic bioactivity are investigated: thermal autolysis, ultrasonication, cell milling and high-pressure homogenization. Thermal yeast autolysis resulted in the highest release of protease activity, with 2.45 ± 0.05 U/g_dm after 3 h incubation at 45 °C. However, autolysis poses challenges for automation, and thus a stop criterion, due to the lack of in-line enzyme activity assays,. While glass bead treatment gave the highest reproducibility, ultrasonication and high-pressure homogenization resulted in comparably high protease activities in the BSY extracts produced. Both methods, in the form of a cell mill and high-pressure homogenizer, are cell disruption methods that are already employed on an industrial scale. It has now been demonstrated that these methods can be used to produce proteolytically active yeast extracts from a previously considered waste stream. Full article

The use of bakery leftovers as a substitute for malt in brewing represents a sustainable approach that reduces costs and waste. In this paper, the fermentation of brewer’s spent grain, a byproduct of beer production, is integrated with the use of non-conventional yeasts to unlock the potential of yeasts beyond the common Saccharomyces species. This creates a circular system where byproducts are efficiently utilized, fostering sustainability and innovation in food production. This study assesses the fermentative capabilities of the non-conventional yeast Yarrowia lipolytica and the lactic acid bacterium Lactobacillus acidophilus DSM 20079 on brewer’s spent grain, a byproduct from brewing beer with old wheat bread and barley malt. Both hydrolyzed with a cell-wall-degrading enzyme complex and non-hydrolyzed brewer’s spent grain were evaluated for key fermentation indicators such as the number of microbial cells, total titratable acidity, pH, reduced sugar content, and fatty acid composition. The findings reveal that Yarrowia lipolytica effectively fermented brewer’s spent grain without prior hydrolysis, maintaining a balanced fatty acid profile. The combined action of both microorganisms provided optimal fermentation outcomes, offering a promising approach for valorizing brewer’s spent grain, reducing waste, and promoting a circular economy in the brewing and food industries. Full article

Yeasts have emerged as an important resource of bioactive compounds, proteins and peptides, polysaccharides and oligosaccharides, vitamin B, and polyphenols. Hundreds of thousands of tons of spent brewer’s yeast with great biological value are produced globally by breweries every year. Hence, streamlining the practical application processes of the bioactive compounds recovered could close a loop in an important bioeconomy value-chain. Cell lysis is a crucial step in the recovery of bioactive compounds such as (glyco)proteins, vitamins, and polysaccharides from yeasts. Besides the soluble intracellular content rich in bioactive molecules, which is released by cell lysis, the yeast cell walls β-glucan, chitin, and mannoproteins present properties that make them good candidates for various applications such as functional food ingredients, dietary supplements, or plant biostimulants. This literature study provides an overview of the lysis methods used to valorize spent brewer’s yeast. The content of yeast extracts and yeast cell walls resulting from cellular disruption of spent brewer’s yeast are discussed in correlation with the biological activities of these fractions and resulting applications. This review highlights the need for a deeper investigation of molecular mechanisms to unleash the potential of spent brewer’s yeast extracts and cell walls to become an important source for a variety of bioactive compounds. Full article

A 60-day feeding experiment was conducted to examine whether (i) soybean meal (SBM) protein in the diet of Nile tilapia (Oreochromis niloticus) can be replaced with protein from spent brewer’s yeast (SBY); (ii) co-rearing with biofloc alters fish growth, feed conversion and protein efficiency compared with rearing in clear water; and (iii) accumulated protein quantity and quality in biofloc acts as a possible feed source for the fish in periods of low feed intake. The fish were reared in either a bio-recirculating aquaculture system (Bio-RAS) or a clear-water RAS (Cw-RAS). In Bio-RAS, the mechanical and biological filters used in Cw-RAS were replaced with an open bioreactor that delivered heterotrophic-based biofloc to the rearing tanks and also acted as a sedimentation trap for effluent water before recirculating it back into the rearing unit. The fish were fed four iso-nitrogenous and iso-energetic diets (~28% crude protein, ~19 MJ kg⁻¹ gross energy) in which SBM protein was replaced with increasing levels of SBY, with triplicate tanks per inclusion level. The results revealed that average fish growth was greater in a biofloc environment compared with clear water and also greater at higher inclusion levels of SBY. However, in both rearing environments, fish growth displayed a second-degree polynomial distribution with increasing SBY inclusion level, with a peak between 30% and 60% inclusion. Fish in the biofloc environment showed better feed conversion ratio and protein retention, likely through ingesting both given feed and biofloc. Biofloc contained a significant amount of accumulated protein with a high biological profile, thereby constituting a possible feed reserve for the fish. A conclusion underlined by the apparent improved feed conversion of Bio-RAS reared fish, where that ingestion of biofloc will reduce the need for external feed per unit growth. Full article

A new subclass of nutraceuticals, called immunoceuticals, is dedicated to immunological regulation. Although yeast-derived β-1,3/1,6-D-glucan shows promise as an immunoceutical candidate, further studies are needed to define its precise immune-enhancing processes and to standardize its use. Following methotrexate (MTX)-induced immunosuppression in rats, we evaluated the immunomodulatory efficacy of a highly pure and standardized β-1,3/1,6-D-glucan sample (YBG) in RAW 264.7 macrophages. In in vitro and in vivo models, YBG demonstrated remarkable immunomodulatory effects, such as repair of immune organ damage, elevation of blood cytokine levels, and enhanced phagocytosis and nitric oxide production in RAW 264.7 cells. These results are consistent with the established immunostimulatory properties of β-glucan. It is noteworthy that this research indicates the potential of YBG as an immunomodulatory nutraceutical, as it is among the first to demonstrate immunological augmentation in an immunosuppression setting produced by MTX. Based on these observations, further investigation of YBG is warranted, particularly given its potential to emerge as a combination immunoceutical to mitigate immunosuppression and reduce the risk of infection in rheumatoid arthritis (RA) patients receiving long-term MTX therapy. Full article

Glucosidases are important enzyme largely used in food industry; for this reason, different research studies have been aimed at investigating new producing microorganisms and cheap growth medium that can help to minimize their production costs and time. Food by-products and wastes are considered low-cost substrates that can play an important role from the perspective of a circular economy concept. Brewer’s spent grain (BSG) is the most abundant by-product of beer production that, thanks to its chemical and nutritional composition, has recently been re-evaluated for its application in various sectors. The aim of the present study was to induce the production of β-glucosidase in Wickerhamomyces anomalus BS91 using BSG as the main component. The results obtained during our research show that BSG is an attractive by-product of beer industry that can be used for the production of glucosidase. Enzyme activity obtained using this microorganism was equal to 369.7 ± 8.0 U/mL, six time greater than that observed in conventional nutritional medium (59.0 ± 5.7 U/mL). Also, we conducted additional research concerning β-glucosidase localization, and the obtained results show that the enzyme is tightly bound to the yeast cell wall, and this can probably greatly affect its stability since it is being protected by the cell wall itself. Full article

Bioethanol, an alcohol produced by microbial fermentation, is traditionally produced from sugar-rich plants such as sugar cane, sugar beet and maize. However, there is growing interest in the use of lignocellulose, an abundant and inexpensive renewable energy source, as a potential substitute for the production of biofuels and biochemicals. Yeast Saccharomyces cerevisiae, which is commonly used for ethanol fermentation, cannot cope with lignocellulose due to a lack of lignocellulolytic enzymes and the inefficient functioning of the pentose phosphate pathway. The aim of this research was to isolate yeasts that can efficiently produce bioethanol and valuable byproducts from both glucose and xylose in a two-stage fermentation process using brewer’s spent grains. This approach should maximize sugar utilization and improve the economic viability of bioethanol production while contributing to waste valorization and sustainability. Kluyveromyces marxianus and Candida krusei were identified and tested with different initial concentrations of glucose and xylose. The results showed that both yeasts produced bioethanol from glucose but were inefficient with xylose, yielding valuable compounds, such as 2,3-butanediol and glycerol instead. A two-stage fermentation was then carried out with weak acidic hydrolysate from brewer’s spent grain. In the first stage, glucose was fermented by S. cerevisiae to produce bioethanol; in the second stage, xylose was fermented by K. marxianus and C. krusei to obtain other valuable products. Full article

Yeast, crucial in beer production, holds great potential owing to its ability to transform into a valuable by-product resource, known as brewer’s spent yeast (BSY), with potentially beneficial physiological effects. This study aimed to compare the composition and soluble polysaccharide content of Brewer’s spent yeast with those of cultured yeast strains, namely Saccharomyces cerevisiae (SC) and S. boulardii (SB), to facilitate the utilization of BSY as an alternative source of functional polysaccharides. BSY exhibited significantly higher carbohydrate content and lower crude protein content than SC and SB cells. The residues recovered through autolysis were 53.11%, 43.83%, and 44.99% for BSY, SC, and SB, respectively. Notably, the polysaccharide content of the BSY residue (641.90 μg/mg) was higher than that of SC (553.52 μg/mg) and SB (591.56 μg/mg). The yields of alkali-extracted water-soluble polysaccharides were 33.62%, 40.76%, and 42.97% for BSY, SC, and SB, respectively, with BSY comprising a comparable proportion of water-soluble saccharides made with SC and SB, including 49.31% mannan and 20.18% β-glucan. Furthermore, BSY demonstrated antioxidant activities, including superoxide dismutase (SOD), ABTS, and DPPH scavenging potential, suggesting its ability to mitigate oxidative stress. BSY also exhibited a significantly higher total phenolic compound content, indicating its potential to act as an effective functional food material. Full article

The European Union’s (EU) agricultural self-sufficiency is challenged by its reliance on imported plant proteins, particularly soy from the Americas, contributing to deforestation and greenhouse gas emissions. Addressing the EU’s protein deficit, this study evaluates alternative protein sources for aquaculture, focusing on their nutritional value, elemental content, and polycyclic aromatic hydrocarbons (PAHs). Protein flours from gastropods (Helix pomatia, Arion lusitanicus, Arion vulgaris) and their hepatopancreas, along with plant-based proteins from food industry by-products (oilcakes, coffee grounds, spent brewer’s yeast), were analyzed. Results revealed that snail flour contained the highest protein content at 59.09%, significantly outperforming hepatopancreas flour at 42.26%. Plant-based proteins demonstrated substantial nutritional value, with coffee grounds flour exhibiting a remarkable protein content of 71.8% and spent brewer’s yeast flour at 57.9%. Elemental analysis indicated high levels of essential minerals such as magnesium in hepatopancreas flour (5719.10 mg/kg) and calcium in slug flour (48,640.11 mg/kg). However, cadmium levels in hepatopancreas flour (11.45 mg/kg) necessitate caution due to potential health risks. PAH concentrations were low across all samples, with the highest total PAH content observed in hepatopancreas flour at 0.0353 µg/kg, suggesting minimal risk of PAH-related toxicity. The analysis of plant-based protein sources, particularly oilcakes derived from sunflower, hemp, flax, and pumpkin seeds, revealed that these by-products not only exhibit high protein contents but present a promising avenue for enhancing the nutritional quality of feed. This study underscores the potential of utilizing gastropod and plant-based by-products as sustainable and nutritionally adequate alternatives to conventional feeds in aquaculture, contributing to the EU’s environmental sustainability goals. Full article