Effects of pH and salt concentration on freeze-thaw fractionation of soymilk protein.

BACKGROUND: The two major storage proteins of soymilk are the globulins 7S and 11S. Freeze-thaw fractionation is a simple method for separating these proteins in raw soymilk. In this study, we assessed the freeze-thaw fractionation ability of raw soymilk under various pH (4.3-11.6) conditions and added salt (sodium chloride) concentrations (0.00-0.67 mol L-1). RESULTS: We successfully achieved fractionation within a pH range of 5.8-6.7 and when the salt concentration was 0.22 mol L-1 or lower. Analysis of particle size distribution and microscopic examination of soymilk revealed no direct correlation between particle size and freeze-thaw fractionation ability. Interestingly, it was confirmed that the ranges of zeta potential values associated with successful freeze-thaw fractionation in raw soymilk remained consistent across different pH and salt concentration conditions. These ranges were between -23 and -28 mV at pH levels ranging from 5.8 to 6.7 and between -18 and -29 mV at added salt concentrations ranging from 0 to 0.22 mol L-1. CONCLUSION: The pH and salt concentration in raw soymilk markedly influence the freeze-thaw fractionation process. We confirmed that the range of zeta potential values where fractionation was possible remained consistent under various pH and salt concentration conditions. These findings suggest that the zeta potential value might serve as an indicator for evaluating the freeze-thaw fractionation ability of raw soymilk. © 2024 Society of Chemical Industry.

Breeding exceptionally fragrant soybeans for soy milk with strong aroma.

Knockout of the soybean (Glycine max) betaine aldehyde dehydrogenase genes GmBADH1 and GmBADH2 using CRISPR/Cas12i3 enhances the aroma of soybeans. Soy milk made from the gmbadh1/2 double mutant seeds exhibits a much stronger aroma, which consumers prefer; this mutant has potential for enhancing quality in soy-based products.

Probiotic Lactiplantibacillus plantarum KU210152 and its fermented soy milk attenuates oxidative stress in neuroblastoma cells.

We evaluated the probiotic properties and neuroprotective effects of Lactiplantibacillus plantarum KU210152 and its application in soy milk. L. plantarum KU210152 exhibited high tolerance to artificial gastrointestinal conditions, high adhesion to intestinal cells (HT-29), and safe enzyme production. Conditioned medium acquired from HT-29 cells treated with heat-killed lactic acid bacteria (LAB-CM) was used to evaluate the neuroprotective effects. The CM exhibited neuroprotective effects via cell viability assay, morphological observations, and suppression of ROS production. Heat-killed L. plantarum KU210152 increased brain-derived neurotrophic factor (BDNF) and tyrosine hydroxylase (TH) expression in HT-29 cells. In SH-SY5Y cells, pretreatment with L. plantarum KU210152 CM decreased Bax/Bcl-2 ratio and upregulated BDNF and TH expression. The CM inhibited caspase-9 and caspase-3 activities. The neuroprotective effects of L. plantarum KU210152 were also confirmed in fermented soy milk. Therefore, both L. plantarum KU210152 and the fermented soy milk can be used as functional ingredients with neuroprotective effects against oxidative stress.

Fluoride Determination in Milk, Soy, and Water-Based Products Using Ion-Selective Electrode and Direct Measurement Technique: Single-Laboratory Validation, First Action 2022.05.

BACKGROUND: The AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals issued a call for methods for the determination of fluoride in infant formula. Standard Method Performance Requirement (SMPR®) 2014.016 was approved. OBJECTIVE: A single-laboratory validation (SLV) of a fluoride ion-selective electrode (F-ISE) method was completed. METHODS: Five powder samples were reconstituted, and hydrochloric acid was added to dissolve and release any bound fluoride. Samples included infant and adult nutritional products made from milk, whey, or soy, containing intact, partially hydrolyzed, or hydrolyzed proteins. Sodium citrate buffer was added to complex any interfering ions and adjust pH and ionic strength. Samples were analyzed in duplicate over 6 days using F-ISE. RESULTS: Results were calculated based on one of two least-squares (log fit) standard curves (0.02 to 0.1 µg/100 g or 0.1 to 2.0 µg/100 g). The LOQ for the method was determined to be 3.3 µg/100 g, which was far below the minimum analytical value of 30 µg/100 g required in the SMPR. The fluoride concentrations ranged from approximately 3 to 14 µg/100 g reconstituted powder and the intermediate precision, RSDr, ranged from 0.7 to 12.4%. Although all of these results are out of scope for the SMPR due to their low fluoride, it should be noted that the RSDr for formulas with fluoride concentrations ranging from approximately 9 to 14 µg/100 g ranged from 0.7 to 4.3%, and the RSDr for the two formulas with fluoride concentrations at or below the theoretical detection limit of the method were only approximately10 and 12.4%. Recoveries ranged from 94 to 98% for samples spiked at three levels with NIST-traceable standard solutions, meeting the SMPR. CONCLUSION: The F-ISE method meets the SMPR and was adopted as a First Action Official MethodSM. HIGHLIGHTS: The fluoride ion-selective electrode method presented here is affordable and easy to run. The addition of acid to the samples dissolves any minerals which may bind the fluoride.

Riboflavin bio-enrichment of soy beverage by selected roseoflavin-resistant and engineered lactic acid bacteria.

Some lactic acid bacteria (LAB) have the ability to synthesize riboflavin, a trait linked to the presence of ribG, ribB, ribA and ribH genes located in the rib operon. Previous screening of riboflavin producers identified several LAB strains belonging to different species with this ability, but none of them surpassed 0.25 mg/L production of the vitamin. In this study, we explored two strategies to obtain riboflavin-overproducing strains: by roseoflavin selection of mutants, and by the transformation of selected strains with plasmids pNZ:TuR.rib or pNZ:TuB.rib containing the genes ribG, ribB, ribA and ribH from Lactococcus cremoris MG1363. The resulting riboflavin-overproducing strains were able to produce yields between 0.5 and 6 mg/L in culture media and several of them were selected for the fermentation of soy beverages. Riboflavin in bio-enriched soy beverages was evaluated by direct fluorescence measurement and high-performance liquid chromatography-fluorescence analysis. Soy beverages fermented with the recombinant strains Lactococcus cremoris ESI 277 pNZ:TuB.rib and Lactococcus lactis INIA 12 pNZ:TuR.rib showed the highest riboflavin yields (>5 mg/L) after 24 h fermentation. On the other hand, roseoflavin-resistant mutant Limosilactobacillus fermentum INIA P143R2 was able to enrich fermented soy beverages with 1.5 mg/L riboflavin. Riboflavin-overproducing LAB strains constitute a good option for riboflavin enrichment of soy beverages by fermentation and the commercialization of such beverages could be very useful to prevent riboflavin deficiency.

Enhancing the functionality of plant-based Yogurt: Integration of lycopene through dual-stage fermentation of soymilk.

Well-defined compositional assemblies of plant-based yogurt are of fast-growing awareness for world population concerning environmental sustainability, economic burdens and health risks. Soybean is an attractive candidate for plant yogurt, suffering from poor flavor, limited nutrition, and undesired allergens to offer healthy-functional segments. Herein, we deciphered a novel lycopene-soy yogurt by efficient two-stage fermentation of engineered B. subtilis and LAB. The fortified sogurt was ensured with redundant lycopene of 22.67 ± 2.95 mg/g DCW by engineered B. subtilis and enriched soy isoflavone from synergistic effects of engineered B. subtilis and LAB, possessing strong antioxidant capacity for upgrading functionality. Moreover, the desired pH, accelerated protein hydrolysis, enhanced amino acid availability, and expected sensory attributes cooperatively conferred lycopene-soy yogurt as healthy functional food. High potential is firstly ascribed to sequential dual culture of engineered B. subtilis and LAB in lycopene-soy yogurt, in which flavorful, hypoallergenic and antioxidative ingredients enabled functionalities for plant-based yogurt.

Quantification of the environmental impact arising from the utilization of whole and defatted Okara in fermentative and dehydration processes.

Okara is the insoluble pulp that remains after the grinding and filtration of soybeans during the production of soymilk and tofu. As it retains a noteworthy quantity of nutrients, there has been an increasing emphasis in the utilization of this residue for the development of sustainable processes. This study focused on assessing the environmental impact of employing okara as a medium for fermenting and dehydrating probiotic bacteria at laboratory scale. The evaluation was carried out using the Life Cycle Assessment (LCA) methodology, considering the entire process lifecycle. Whole okara and defatted okara were used as culture media for Lactiplantibacillus plantarum CIDCA 83114, followed by dehydration (either freeze-drying or spray-drying) and subsequent storage. For the purpose of comparison, both scenarios (whole and defatted okara) were evaluated using 1 kg of dehydrated final product for storage, as functional unit. Based on experimental results, the conservation of the received okara and the dehydration-storage (e.g., freezing and freeze-drying) phases were identified as the most significant environmental hotspots responsible for the most substantial impacts of the processes. The use of LCA facilitated the measurement of the environmental effects linked to the reutilization of okara as an agro-industrial residue, thus providing quantitative support when engineering its sustainable valorization.

Comparison between hydrodynamic and ultrasound cavitation on the inactivation of lipoxygenase and physicochemical properties of soy milk.

The effects of hydrodynamic cavitation (HC) and ultrasound cavitation (UC) on the lipoxygenase activity and physicochemical properties of soy milk were evaluated. The results revealed that both ultrasound cavitation and hydrodynamic cavitation significantly inactivated the lipoxygenase activity. After the exposure to ultrasound cavitation at 522.5 W/L and 70 °C for 12 min, the lipoxygenase activity was inactivated by 96.47 %. Meanwhile, HC treatment with the cavitation number of 0.0133 for 240 min led to the loss of 79.31 % of lipoxygenase activity. An artificial neural network was used to model and visualize the effects of different parameters after ultrasound cavitation treatment on the inactivation efficiency of soy milk. Turbiscan test results showed that hydrodynamic and ultrasound cavitation decreased the instability index and particle size of soy milk. Moreover, the total free amino acid content was significantly increased after hydrodynamic and ultrasound cavitation treatment. Gas chromatography-mass spectrometry showed that the total content of beany flavor compounds decreased after acoustic cavitation and HC treatment. Acoustic cavitation and HC affected the tertiary and secondary structure of soy milk, which was related to the inactivation of lipoxygenase. We aim to explore a potential and effective way of the application in soy milk processing by comparing the ultrasound equipped with heat treatment and hydrodymic cavitation.

An Investigation into the Performance and Mechanisms of Soymilk-Sized Handmade Xuan Paper at Different Concentrations of Soymilk.

Invaluable paper relics that embody a rich traditional culture have suffered damage, requiring urgent restoration. In this context, the utilization of soymilk as a sizing agent holds great significance and reverence. This study investigates the use of soymilk as a sizing agent for Xuan paper and evaluates its effects on various properties and the long-term behavior of the paper. The findings reveal that the application of soymilk as a sizing agent for Xuan paper imparts distinct properties, including hydrophobicity, improved mechanical properties, and unique chromaticity. These characteristics-arising from the papillae on the surface of the Xuan paper, the protein folding of the soy protein, and hydrogen-bonding interactions between the soy protein and paper fibers-play a crucial role in shaping the paper's unique attributes. From a physicochemical perspective, the aging process leads to multiple changes in paper properties. These changes include acidification, which refers to a decrease in pH, as well as a decline in mechanical strength, an increase in chromaticity, and a decrease in the degree of polymerization (DP) of the paper. The Ekenstam equation is employed to predict the lifespan of the paper, showing longer lifespans for Sheng Xuan paper and a negative correlation between soymilk concentration and lifespan in soymilk-sized paper. Our work provides valuable insights for the preservation and maintenance of paper, highlighting the potential benefits and challenges of using soymilk for surface sizing.

Characterizing acidified and renneted gels with different soy milk and skim milk proportions.

To understand the properties of differently acidified and renneted gels with different soy milk and skim milk proportions, mixed milks were prepared and treated using sequenced renneting then acidification at 4 °C, and the formation, spontaneous whey separation, and microstructure of the gels were monitored. The results showed that both acidification and renneting promoted gel formation in mixed milk and increased gel strength. In gels, the pH range was narrow (pH ≤ 5.2) at low soy milk proportion (25%) and low renneting degrees (0%, 25% and 50%), and the pH range was extended such that gels were formed with increasing soy milk proportion and renneting degree. When compared with pH, soy milk proportion and renneting degree influenced whey separation percentages more strongly. Soy milk significantly reduced whey separation percentages in gels, and gel strength was highest at 50% soy milk. Protein aggregates sizes increased with increasing soy milk proportion at the 75% renneting degree, and the pore sizes of skim milk-dominated gels was strongly influenced by acidification. These results help us understand mixed gel properties and provide valuable information for the manufacture of mixed fermented dairy products.

Evaluation of nutritional and physicochemical characteristics of soy yogurt by Lactobacillus plantarum KU985432 and Saccharomyces boulardii CNCMI-745.

Nutritional yeast-produced soy yogurt has grown in demand, because of its unique nutritional and health benefits. It has low cholesterol, no lactose, and high levels of protein, probiotic yeast, vitamins, and minerals. In this work, Soymilk (12.5%) was prepared and fermented to produce soy yogurt. Growth curves, probiotic characteristics of Saccharomyces boulardii CNCMI-745 and Lactobacillus plantarum KU985432 were determined. The nutritional value of both yogurts was evaluated, including viable cell count, protein, vitamin B-complex, sugars, phenolic acids, and fatty acids, mineral content, stability, and storage. Analysis of the physicochemical composition of the yogurts included assessment of titratable acidity, antioxidant potential, viscosity, and moisture content. The probiotic viable count of the produced yogurts met the standards for commercial yogurts. S. boulardii CNCMI-745 displayed safety characteristics and high tolerance to heat, acid, and alkaline stress. The produced B vitamins increased in both yogurts. The total saturated fatty acids in Saccharomyces-yogurt decreased, while the unsaturated fatty acids increased. Saccharomyces-yogurt showed high antioxidant activity, phenolic acids, and crude protein content. Both yogurts demonstrated the same tendency for stability during 16 day-storage. In conclusion, using nutritional yeast in the production of soy yogurt increased its nutritional content more than probiotic lactic acid bacteria.

Nutritional and functional insight into novel probiotic lycopene-soy milk by genome edited Bacillus subtilis.

Nutritional and functional soy-based milk gains growing attention globally in food industry. However, its poor sensorial attributes, single flavor, and limited substance variety become critical issues in displaying balanced nutrition and multifunction for health. Herein, a novel probiotic lycopene-soy milk was developed by genome edited Bacillus subtilis harboring lycopene biosynthesis cassette with efficient lycopene production of 25.73 ±â€¯1.57 mg/g DCW. Further investigation displayed desirable pH, reducing sugar, protein, total phenolic content and isoflavone for achieved milk than conventional soy milk, implying it with well-balanced nutritional quality. Notably, achieved milk exhibited stronger antioxidant capacity and higher isoflavone bioavailability for functionality. Moreover, it possessed significantly high scores for taste, appearance, and overall acceptability, suggesting its excellent sensorial attributes. To our delight, it is the first time to fortify soy-milk with probiotic and lycopene by genome edited B. subtilis to explore additive effect on improving nutritional value and functionality for food application.

Enhanced Cholesterol-Lowering and Antioxidant Activities of Soymilk by Fermentation with Lactiplantibacillus plantarum KML06.

This study aimed to evaluate the cholesterol-lowering and antioxidant activities of soymilk fermented with probiotic Lactobacillaceae strains and to investigate the production of related bioactive compounds. Lactiplantibacillus plantarum KML06 (KML06) was selected for the fermentation of soymilk because it has the highest antioxidant, cholesterol-lowering, and ß-glucosidase activities among the 10 Lactobacillaceae strains isolated from kimchi. The genomic information of strain KML06 was analyzed. Moreover, soymilk fermented with KML06 was evaluated for growth kinetics, metabolism, and functional characteristics during the fermentation period. The number of viable cells, which was similar to the results of radical scavenging activities and cholesterol assimilation, as well as the amount of soy isoflavone aglycones, daidzein, and genistein, was the highest at 12 h of fermentation. These results indicate that soymilk fermented with KML06 can prevent oxidative stress and cholesterol-related problems through the production of soy isoflavone aglycones.

Perceptions and knowledge of protein in dairy and plant-based alternatives among stakeholders in the US marketplace.

This study explores beliefs about protein in dairy and plant-based (PB) alternatives among stakeholders in the US marketplace and whether beliefs are associated with product preferences. Eight thousand and fifty-two unique comments submitted to the US Food and Drug Administration (FDA) in response to a request for public input on the labelling of PB dairy alternatives (FDA-2018-N-3522) were coded. Of these, 383 (4.8%) discussed protein and were analysed for protein-specific themes. Themes were examined in relation to the submitter's product preference. Most comments that discussed protein focused on protein content and/or health outcomes believed to be associated with intake. Only one commenter who preferred dairy demonstrated an inaccurate understanding of protein content in dairy and PB alternatives, although nearly all failed to identify fortified soy beverage as an appropriate protein replacement; meanwhile, 14.2% who preferred PB alternatives demonstrated an inaccurate understanding regarding protein content in dairy and PB products. The results suggest knowledge gaps exist regarding protein in PB dairy alternatives, especially among those who prefer non-dairy options.

Soy Milk Consumption in the United States of America: An NHANES Data Report.

With the increasing adoption of plant-based diets in the United States, more and more individuals replace cow milk with plant-based milk alternatives. Soy milk is a commonly used cow milk substitute, which is characterized by a higher content of polyunsaturated fatty acids and fibers. Despite these favorable characteristics, little is known about the current prevalence of soy milk consumption the United States. We used data from the National Health and Nutrition Examination Surveys (NHANES) to assess soy milk usage in the United States and identified potential predictors for its consumption in the US general population. The proportion of individuals reporting soy milk consumption in the NHANES 2015-2016 cycle was 2%, and 1.54% in the NHANES 2017-2020 cycle. Non-Hispanic Asian and Black ethnicities (as well as other Hispanic and Mexican American ethnicities in the 2017-2020 cycle) significantly increased the odds for soy milk consumption. While a college degree and weekly moderate physical activity were associated with significantly higher odds for consuming soy milk (OR: 2.21 and 2.36, respectively), sex was not an important predictor. In light of the putative health benefits of soy milk and its more favorable environmental impact as compared to cow milk, future investigations should attempt to identify strategies that may help promote its consumption in selected populations.

Effect of cavitation jet technology on instant solubility characteristics of soymilk flour: Based on the change of protein conformation in soymilk.

The protein conformation of soymilk is the key to affecting the instant solubility of soymilk flour. This study aimed to evaluate the effect of cavitation jet treatment time (0, 2, 4, 6, and 8 min) on the instant solubility of soymilk flour based on the conformational changes of protein in soymilk. The results showed that the cavitation jet treatment for 0-4 min significantly unfolded the protein structure of soymilk and increased the content of soluble protein, which reduced the particle size and increased the electrostaticrepulsion and the viscosity of soymilk. This was beneficial for soymilk droplets fully atomized and repolymerized in the spray drying tower, forming soymilk flour particles with large size, smooth surface, and uniform distribution. When the cavitation jet treatment time was 4 min, the wettability (from 127.3 ± 2.5 s to 84.7 ± 2.1 s), dispersibility (from 70.0 ± 2.0 s to 55.7 ± 2.1 s), and solubility (from 56.54% to 78.10%) of soymilk flour were significantly improved. However, when the time of the cavitation jet treatment was extended to 8 min, the protein of soymilk aggregated and the stability of soymilk decreased, which reduced the particle size and hurt the surfacecharacteristics of soymilk flour after spraydrying. It resulted in a decrease in the instant solubility of soymilk flour. Therefore, the cavitationjet treatment with proper time increases the instant solubility of soymilk flour by improving the protein conformation of soymilk.

[Soy beverages and women's health: evidence review and experts opinion]. / Bebidas de soja y salud femenina. Revisión de la evidencia y opinión de expertos.

Introduction: Soy drinks are an increasingly consumed option within the Western diet. However, there are concerns about potential endocrine disruptor effects and possible impact on women's reproductive health. This review evaluates scientific documents in gynecology and obstetrics under an evidence-based medicine approach. All methods adhered to PRISMA 2020 declaration guidelines. The evaluated studies do not support a positive association between soy intake and early puberty or breast cancer; instead, a protective effect against such neoplasm was observed. Transplacental passage of soy isoflavones and their presence in breast milk has been reported without any maternal-fetal complications nor congenital malformations. Exposure to soy-derived products appears to have a neutral effect on body weight and bone health. Studies performed in adults indicate that soy may promote a minimal increase in thyrotropin (TSH) in subjects with subclinical hypothyroidism. The impact of soy-based foods on gut microbiota appears favorable, especially when consuming fermented products. Many of the human studies have been conducted with isoflavones supplements, isolated or textured soy proteins. Therefore, the results and conclusions should be interpreted cautiously, as these are not entirely applicable to commercial soy beverages.

Introducción: Las bebidas vegetales de soja constituyen una alternativa dentro de la dieta habitual. Sin embargo, existe la preocupación de potenciales efectos en la salud reproductiva de la mujer por mecanismos de disrupción endócrina. En esta revisión se evalúan documentos científicos en el área de la Ginecología y la Obstetricia bajo el tamiz de la medicina basada en la evidencia, respondiendo preguntas estructuradas. La metodología se apegó a las guías establecidas por la declaración PRISMA 2020. Los estudios evaluados descartan un riesgo incrementado de pubertad precoz o cáncer de mama; incluso se aprecia un efecto protector frente a dicha neoplasia. Se ha reportado el paso transplacentario de isoflavonas de soja y su presencia en la leche materna, sin que ello implique una relación con complicaciones materno-fetales o malformaciones congénitas. La exposición a productos de soja no parece influir sobre el peso corporal y la salud ósea de la mujer. Los estudios en adultos indican que la soja favorece un mínimo incremento de tirotropina (TSH) en personas con antecedente de hipotiroidismo subclínico. El impacto de los alimentos basados en soja sobre la microbiota intestinal parece ser favorable para su diversidad, particularmente al consumir productos fermentados. Muchos de los estudios en humanos han sido realizados con suplementos de isoflavonas o con productos que contienen proteínas aisladas o texturizadas de soja. Por tanto, los resultados y las conclusiones deben interpretarse con cautela ya que no son totalmente extrapolables a las bebidas comerciales de soja.

Mechanism of the glucono-δ-lactone induced soymilk gelation: Enthalpy and entropy transformation in the cross-linking of protein molecules.

This study aimed to explore new techniques to regulate the quality of soy products. The glucono-δ-lactone (GDL) induced soymilk gelation process and the gel network structure characteristic were compared as a matter of temperature, and the role of reaction kinetics was discussed. Results showed that there were similarities in the development of G' curves under different temperatures, whereas the gel network structures and the energy requirements of cross-linking reactions were different. In the high-temperature region (70 °C-95 °C), the exposure and binding of reactive groups were promoted. The activation enthalpy (ΔH*) required by protein aggregates decreased and the effect of entropy reduction (-TΔS*) was enhanced, which led to shorten the preaggregation time (tg) and increase the gelation rate (k), resulting in the formation of rough, porous gel network with high stiffness. By contrast, in the low-temperature region (40 °C-70 °C), high enthalpy contributions and low entropy changes were required, then a fine, soft, and tender gel network formed. Besides, a funnel-shaped model of the enthalpy-entropy energy transformation mechanism of soymilk gelation was proposed. The results of this study revealed that adjusting the enthalpy-entropy energy requirements of the protein cross-linking reaction could be utilized to the regulation of the network structure and quality of soymilk gels, which could enrich the reaction kinetics theory and provide innovative ideas for food quality control technology from the perspective of energy requirement and energy input.

Effect of fermented soy beverage in aged female mice model.

Soy beverage is a rich source of phytoestrogens isoflavones, with potential benefits on health. The effect of those compounds depends greatly on their bacterial metabolization into their aglycone forms. This study evaluated the health effects of two soy beverages, non-fermented (SB) and fermented with Bifidobacterium pseudocatenulatum INIA P815 (FSB), in acyclic and cyclic C57BL/6J aged female mice as a model of menopause and premenopause, respectively. SB and FSB treatments were administrated for 36 days and, subsequently, body weight, lipid and inflammatory profile and fertility were analyzed and compared. In addition, hepatic gene expression and faecal microbiota composition were also assessed. After fermentation, FSB presented a high content in the aglycones daidzein and genistein and a higher antioxidant activity. FSB treated cyclic mice showed a significant increase in the number of retrieved oocytes and zigotes. Differences in serum lipids were observed in triglycerides, which were lower in FSB than in SB groups. None of the treatments influenced the inflammatory profile or caused a dramatic change in the intestinal microbiota profile or hepatic gene expression in any of the groups. Our data showed that FSB provided greater health benefits than SB in lipid profile and fertility in cyclic mice. These beneficial effects could be attributed to the fermentation process, which produces more bioavailable and bioactive compounds, achieving a greater impact on health.

Effect of a co-fermentation system with high-GABA-yielding strains on soymilk properties: microbiological, physicochemical, and aromatic characterisations.

Biosynthesis is the safest method for preparing GABA; however, there are not enough GABA-producing strains to provide an effective resource. The purpose of this study was to determine the feasibility of using Lactobacillus fermentum SMN10-3(A) and Lactococcus lactis SMN15-6(B) to study the effects of strain complex pairing on the GABA formation, flavour, and metabolic pathways of fermented soymilk. It was found that group A2B1 had the highest acid production rate, GABA yield (1.76 ± 0.01 mg/mL), and flavour compound content. A total of 55 differential metabolites were produced after fermentation, of which 28 dominated by hexanal were significantly downregulated and 26 dominated by alcohols were significantly upregulated. The significant metabolic pathways involved were d-alanine, taurine and hypotaurine, and selenocompound metabolism. Finally, the components contributing to the aroma of fermented soymilk were identified, which included 2-pentylfuran and 2-butyl-2-octenal. These results provide a theoretical basis for future research on GABA-rich fermented foods.