Probiotic fermentation of soybeans and use of fermented soy in cookies.

2025-12-24
Journal of the science of food and agriculture 106(5)

PubMed: 41443672
DOI: 10.1002/jsfa.70409

Study Design

Population: soybeans; cookie formulations
Methods: Lactococcus lactis (LL) and Lactiplantibacillus plantarum (LP) were used to ferment soybeans; soybean flour fermented by LL was incorporated into cookie formulations to evaluate spread factor, hardness, and GABA content

Background

With increasing prevalence of mental health issues such as insomnia and anxiety, γ-aminobutyric acid (GABA) has gained attention for its neurological benefits. The development of GABA-rich functional foods has emerged as a promising research direction. Soybeans, rich in glutamate, are excellent substrates for GABA biosynthesis using microbial fermentation. In this study, Lactococcus lactis (LL) and Lactiplantibacillus plantarum (LP) were used to ferment soybeans, aiming to enhance GABA production. The effects of fermentation on pH value, yield, colony-forming unit, phytic acid content, total phenol content, and ABTS⁺ free radical scavenging activity were investigated. Additionally, soybean flour fermented by LL was incorporated into cookie formulations to evaluate its effects on cookie spread factor and hardness. The GABA content of the cookies was also analyzed.

Results

Co-fermentation with LL and LP significantly reduced phytic acid levels. Mono-fermentation with LL showed higher probiotic viability, better retention of total phenolics and antioxidant capacity, and superior GABA accumulation. Cookies supplemented with LL-fermented soybean flour better maintained the hardness and exhibited a higher GABA content compared to those prepared with unfermented soybean flour (P < 0.05).

Conclusion

Fermentation with LL effectively enhanced GABA content (P < 0.05) and preserved cookie texture comparable to that of 100% wheat flour cookies. These results can support the potential of LL fermentation in developing GABA-enriched plant-based functional foods. © 2025 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Research Insights

Supplement	Dose	Health Outcome	Effect Type	Effect Size	Source
Lactiplantibacillus plantarum LP-01	—	Increased GABA Production	Beneficial	Moderate	View source Mono-fermentation with LL showed higher probiotic viability, better retention of total phenolics and antioxidant capacity, and superior GABA accumulation. Cookies supplemented with LL-fermented soybean flour better maintained the hardness and exhibited a higher GABA content compared to those prepared with unfermented soybean flour
Lactococcus lactis LL-23	—	Increased GABA Content	Beneficial	Moderate	View source Mono-fermentation with LL showed higher probiotic viability, better retention of total phenolics and antioxidant capacity, and superior GABA accumulation. Cookies supplemented with LL-fermented soybean flour better maintained the hardness and exhibited a higher GABA content compared to those prepared with unfermented soybean flour (P < 0.05).