Study of microbial and physicochemical properties of yogurt containing oat milk

In recent years, due to their health benefits, probiotics are considered significantly. Keeping a large number of probiotic bacteria alive until the expiration date is necessary to provide health benefits. Oat, due to its soluble and insoluble fiber content and high fermentation ability by lactic bacteria, is considered significantly. The aim of this study was to investigate the effect of oat milk as a prebiotic, in production of functional yogurt as a new food product and study its microbial and physicochemical properties. In this study, the replacement of 0, 10, 15 and 20% (v/v) oat milk with low-fat milk (2.5%) was performed and its effect on the viability of Lactobacillus acidophilus LA-5 and starter cultures bacteria (Lactobacillus bulgaricus and streptococcus thermophilus) and physicochemical properties of probiotic yogurt during 21 days of storage (days 1, 7, 14 and 21) was investigated. Results showed samples pH decreased with adding oat milk and acidity and viability of Lactobacillus acidophilus LA-5 bacteria increased. Generally, in all of the samples during storage period, total count of probiotic bacteria and starter cultures and pH were reduced and acidity was increased. Results showed that samples viscosity decreases by increasing the percentage of oat milk in yogurt. Yogurt containing 20% oat milk showed highest viability of lactobacillus acidophilus LA-5 during all days of storage.