OBJECTIVE: The probiotic characteristics of the microorganisms (Lactobacillus bulgaricus and Streptococcus thermophillus) used to produce soy yogurt supplemented with prebiotic fructooligosaccharides were evaluated and also the physicochemical and microbiological characteristics and acceptance of the product. METHODS: The formulation containing powdered soy extract, supplemented with fructooligosaccharides (oligofructose and inulin), was fermented for 6 hours (42ºC) and then characterized and compared to a soy yogurt formulation made without supplementation. RESULTS: The starter used to prepare the yogurts (Lactobacillus bulgaricus and Streptococcus thermophillus) showed resistance to bile and to acid. The prebiotics maintained the viability of the lactic acid bacteria at levels higher than necessary to characterize the product as a probiotic food, up to the 28th day of storage. The final pH value of the supplemented yogurt was 4.63, the acidity 0.37% and the acceptance 71.20%. The supplemented yogurt showed greater viscosity, cohesiveness and adhesiveness than the non-supplemented product and was less hard. CONCLUSION: Lactobacillus bulgaricus and Streptococcus thermophillus are probiotics and fructooligosaccharides are ingredients that maintain the viability of lactic acid bacteria in soy yogurt, giving rise to a product with good acceptability.
inulin; yogurt; oligosaccharides; probiotics; soy
