EFFECT OF SOME STABILIZERS ON THE QUALITY AND STORAGE STABILITY OF YOGHURT

Abstract

The main aim of this dissertation was to prepare yoghurt with 2% starter culture of Lactobacillus acidophilus and Streptococcus thermophilus and evaluate its sensory and physiochemical properties. Stabilizers (pectin, guar gum and carboxymethyl cellulose) were used in this study at the rate of 0.1%, 0.2% and 0.3% each. These samples were optimized based on sensory attributes i.e., appearance/color, flavor, texture/mouthfeel, and overall acceptability. Sensory data were analyzed by two-way ANOVA (no blocking) using GenStat and means were compared using LSD at 5% level of significance. Again, yoghurt with optimized stabilizers were compared based on sensory attributes i.e., appearance/color, flavor, texture/mouthfeel, and overall acceptability. Sensory data were analyzed by two-way ANOVA (no blocking) using GenStat and means were compared using LSD at 5% level of significance. From sensory evaluation, Sample coded as G (0.1% CMC) was found to be significantly (p<0.05) superior in sensory quality. The moisture, protein, fat, ash, acidity, pH, and lactose of this formulation were found to be 83%, 3.13%, 2.57%, 0.84%, 0.72%, 4.5 and 3.77% respectively. The shelf life of this product was estimated in terms of pH, syneresis and total plate count, and the shelf life for the best sample was found to be 11 days at refrigerated temperature (5°C).