Enumeration of microflora from ingredients and Idli batter

Microorganisms are responsible for characteristic changes in the fermented foods. They result in the sequential changes during fermentation of food, resulting in souring, leavening and changes in flavour, body and texture. The present study was aimed to enumerate the natural microflora present in raw ingredients used as well in fresh and fermented idli batter.

Study was conducted during the period 2019–2020 to develop solid state fermented cultures for whey based idli batter at Department of Dairy Microbiology, Dairy Science College, Bangalore. The raw ingredients used for idli preparation were sourced from local market of Bangalore. Lactic counts such as leuconostoc, enterococci, pediococci and lactobacilli, as well as yeast counts were enumerated using different selective media by pour plate method.

The leuconostoc count of rice rava, black gram dhal and fresh idli batter on sucrose agar ranged from 2.0 to 3.78 log₁₀ cfu/g; Lactobacilli count on MRS agar varied from 2.0 to 4.11 log₁₀ cfu/g. Yeast count on potato dextrose agar ranged from 1.6 to 2.3 log₁₀ cfu/g. Lactic counts (includes leuconostoc, lactobacillus, pediococci, enterococci) in fresh idli batter ranged from 3.63 log₁₀ cfu/g to 4.77 log₁₀ cfu/g, whereas in fermented idli batter varied from 2.56 log₁₀ cfu/g to 8.74 log₁₀ cfu/g. The yeast counts in fermented batter ranged from 9.23 to 9.56 log₁₀ cfu/g.