Accelerated fermentation of 'idli' batter using soy residue okara.

The aim of this work was to reduce the natural fermentation period of 'idli' from the conventional 14 h to 10 h by adding underutilized okara for the preparation of 'idli'. Black gram was partially substituted with soy residue okara in the ratio of (1:1). After 14 h of natural fermentation, the pH and total acidity of control 'idli' batter was 4.51 and 0.64% and that of okara fortified 'idli' batter was 4.53 and 0.43%, respectively. The amount of CO2 released by the control and okara fortified batter was 19.7% and 33.6% respectively. The viable count of yeast and mold, lactics and mesophilic bacteria in control & okara batter increased with time reaching 9.00 & 10.34, 8.66 & 7.69, and 8.65 & 9.47 log10 cfu/g, respectively at the end of 10 h of natural fermentation. Okara fortified 'idli' was soft and spongy compared to control 'idli' .