Effects of cold storage time on the quality and active probiotics of yogurt fermented by Bifidobacterium lactis and commercial bacteria Danisco.

In this study, the commercial bacteria Danisco and Bifidobacterium lactis were used to ferment soy yogurt, and then the quality of yogurt and the number of active probiotics in yogurt during storage were investigated. The results showed that the total number of viable bacteria in soy yogurt increased first and then decreased, but all of them met the standard for the number of viable bacteria in probiotic foods. The content of protein, lipid, and total sugar in soy yogurt decreased gradually with the extension of storage time. The texture, water holding capacity, and rheological properties of soy yogurt were improved within 0-10 days, and there was no significant change after 15 days. However, brightness and whiteness of yogurt were significantly reduced. Based on realizing the reuse of soy whey, this study provided a theoretical basis for the research of the shelf life of soy yogurt. PRACTICAL APPLICATION: This study developed a soy yogurt with good quality and provided a theoretical basis for the study of the shelf life of soy yogurt. In addition, some technical support was provided for the reuse of soy whey.