Studies on Effect of Initial pH, Storage Temperature and Preservatives on Shelf Life of Yoghurt

Abstract

The yoghurt was prepared from 4.5% fat standardized milk by inoculating with starter culture comprising Streptococcus thermophillus and lactobacillus bulgaricus at 2% and incubated for different periods of time to yield yoghurt of 4.5±0.1, 4.2±0.1 and 3.9±0.1 initial pH and stored at different temperatures of 4, 10 and at 370C for 4, 2 and 1 day respectively. One control sample of 4.5±0.1 initial pH was stored at 40C for 4 weeks as a check. It was observed that initial pH, storage temperature and preservatives had the effect on shelf life and quality of yoghurt.