OPTIMIZATION OF SMP AND SUGAR PROPORTION FOR WHEY BASED YOGHURT AND ITS QUALITY EVALUATION

Abstract

The main aim of this dissertation is to optimization of proportion of SMP and sugar for whey based yoghurt and its quality evaluation. Response surface methodology (RSM) was adopted for optimization of SMP and sugar for the preparation of whey based yoghurt with percentage syneresis, appearance, texture and overall acceptability as response. Paneer whey pH adjusted to 6.8 was used for preparation of yoghurt. Whey based yoghurts prepared from eleven treatment combinations varying SMP (8-14%) and sugar (2-6%) obtained from Central Composite Design using experimental design version 11 was subjected to RSM analysis for optimization. Four optimized formulations solutions having SMP and sugar as coded A (14% SMP and 2% sugar), B (14% SMP and 2.22% sugar), C (14% SMP and 2.65% sugar) and D (14% SMP and 3.46% sugar) obtained after RSM, were prepared for whey based yoghurt and subjected to sensory analysis comparing to control yoghurt from milk as coded E (4% SMP and 3% sugar). The results revealed that addition of SMP rather but not the sugar had significant linear effect on reducing percentage syneresis of whey based yoghurt. Similarly, the addition of SMP rather but not sugar had significant linear effect on increasing average score of both texture and overall acceptability of whey based yoghurt. But, the addition of SMP had significant linear effect on increasing average score of appearance of whey based yoghurt. While, the addition of sugar have significant linear effect on decreasing average score of appearance of whey based yoghurt. From RSM and sensory evaluation, addition of 14% SMP and 3.46% sugar provided the whey based yoghurt best in terms of sensorial properties, had having minimum syneresis, maximum appearance, maximum texture, maximum overall acceptability and contain protein, fat, acidity, total solid, lactose, ash, moisture and pH were found 5.26%, 0.4%, 1.06%, 24.28%, 6.82%, 1.76%, 75.79% and 4.07 respectively