Use of the backslopping method for accelerated and nutritionally enriched idli fermentation.

Abstract

Idli is a cereal-legume-based fermented food, widely consumed in India. It is popular for its nutritional content, sour taste and appetising aroma. The fermentation time of idli batter varies from 12 to 14 h. A reduction in fermentation time of idli batter is of great significance for large-scale idli production units since it will reduce the batch time and will lead to a greater output. Accelerated fermentation can be potentially achieved by using the backslopping method. The inoculum for backslopping was optimally fermented (12 h) idli batter, dried at room temperature. Backslopping reduced the fermentation time of idli batter from the conventional 12 h to 3 h while successfully maintaining sensory attributes of the product. In the idlis prepared by backslopped expedited batter, thiamine was found to be 50% higher; while reduction of anti-nutrients phytate (11%) and trypsin inhibitor (16%) was higher than the conventionally fermented (12 h) idli batter. Backslopping not only accelerated idli batter fermentation but also enhanced its nutritional value. A similar process can be designed for other fermented foods, to expedite fermentation thus reducing the time requirement.