Optimization of Fermentation Parameters to Reduce Fermentation Time of Idli Batter Using RSM

Cereals and legume based foods are a major source of economical dietary energy and nutrients, worldwide. One of the popular among them is idli, fermented steamed product with a soft and spongy texture which is highly popular and widely consumed as a snack food item in India. The predicted variables for the preparation of idli batter were, blend ratio (310.5, 311, 311.5), alpha amylase (5, 10, 15U) and starter culture ratio (10, 01, 11) were taken into account. Designed experiments were conducted randomly to find the effect of these variables on pH and titrable acidity. The pH of fermented idli batter varied from 3.1 to 4.6 and titrable acidity was in range of 0.401 to 2.211 %. Optimum value of levels of predicted variables obtained by compromise optimization of the responses were, 310.5 blend ratio, 15U alpha amylase and 0.051.95 starter culture ratio.