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

Abstract

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.

The role of fermentation with lactic acid bacteria in quality and health effects of plant‐based dairy analogues

“…Fermentation of soybean milk by Lpb. plantarum led to an increase in the amounts of phenolic acids such as gallic, protocatechuic, syringic, and vanillic acids, and fermented soybean milk exhibited 31.7% more ABTS (2,2'-azino-bis-(3-ethylbenzothiazoline-6sulfonic) acid) radical cation scavenging activity than unfermented soybean milk (Mehaya et al, 2023). Similarly, total phenolic content and DPPH radical scavenging activ-ity of oat extract increased from 0.70 to 1.04 mg GAE/g and from 2.14 to 3.56 µmol of TE/g, respectively, after fermentation with Lpb.…”