Optimization of process parameters for pickle masala flavored probiotic Greek yoghurt

Abstract

: In this study, Greek yoghurt was developed using standardized homogenized milk and fermented with suitable indigenous starter culture with optimized process parameters and pickle masala as novel flavor. The product was prepared by fermenting with four culture. Suitability of starters was evaluated based on starter culture counts, pH, titratable acidity and sensory parameters of the Greek yoghurt. The C4 starter containing Streptococcus thermophilus MTCC 5460, Lactobacillus bulgaricus NCIM 2358 and Lactobacillus helveticus MTCC 5463 (probiotic strain) was found to be most suitable as it received significantly (P<0.05) highest score for lactobacilli count (8.86 log CFU/ml), TS (23.41 %) and overall acceptability (8.88) compared to remaining. Among the straining period viz, 15 min, 30 min and 55 min, product prepared by straining for a period of 30 min was optimized based on pH (4.67), titratable acidity (% 0.89 LA) and overall acceptability scores (8.71). No significant effect of various straining period was observed on starter counts of the product. Pickle masala was used as novel flavor and it was added at the rate of 1 %, 1.5 % and 2 % of final product. The increased rate of pickle masala in Greek yoghurt affected adversely on starter count as well as sensory profile. So, 1% rate of addition of pickle masala in Greek yoghurt as flavor was considered more suitable having lactobacilli count (9.05 log CFU/ml), streptococci count (10.37 log CFU/ml), pH (4.81), titratable acidity (0.90 % LA) and overall acceptability score (8.80) compared to other. The composition of optimized Greek yoghurt was TS (23.02 %), fat (7.92 %), protein (6.17 %), lactose (4.91 %), calcium (171 mg/100g) and ash (1.29 %).