Beverage probiotic preparation on the pier whey using Lactobacillus casei (GG) and Streptococcus thermophilus

The enrichment with probiotics is useful method for prevention of various diseases. In this study used whey as it's beneficial nutritional properties, for providing a probiotic beverage. Stereptococcus thermophilus and Lactobacillus casei were prepared from food and during control department. In first step obtained the number of initial inoculum of each bacteria (108 cfu/ml) using spectrophotometery (OD: 1/52), then inoculated (102 cfu/ml) to sterile whey powder broth. In second step, the growth kinetics of bacteria determined in different temperatures (4, 25, 37)°C during 32hr with used 2 hour intervals cultured pour plate colony count (SCD Agar and MRS Agar), respectively. The results indicated that kinetic growth of two bacteria were the same in 0, 12, 18 hours (p≤0.05) and after it the numbers of each bacteria remained 107 cfu/ml. In third step (for stability test) the numbers of two bacteria and pH whey broth measurement, obtained at different temperature (4, 25, 37)°C during 14 days. In result, the bacterial growth were the same 107-108 cfu/ml) and pH changes were (5.8, 4.4, 4.8) respectively. At fourth step the evaluation of organoleptic test was done based on consistency and flavor (taste and smell) with different ratio of L:S (1:1, 1:2, 2:1). The best group was the group 1:1. So, this probiotic beverage based on whey is useful for purpose of industrial production.