Rheological behavior of indian traditional fermented wheat batters used for preparation of Kurdi & Seera
Abstract
Traditional Indian cereal based fermented food products like Kurdi (Maharashtra) and Seera (Himachal Pradesh) are prepared from batter of fermented wheat grains. These wheat batters were prepared by soaking wheat grains (Triticum Astivum L., variety: PBN51) in water at different temperatures (30, 37.5 and 45°C) for four days (natural fermentation), crushed, centrifuged and characterized for rheological properties. The present study was aimed to test the effect of soaking temperature (during natural fermentation of wheat grains) on the rheological behavior of wheat batter. It was determined that viscosity and yield stress of the wheat batter decreased with increase in soaking temperature of natural fermentation. Yield stress decreased by 65% and
82% for wheat grains soaked at 37.5°C and 45°C, respectively as compared to those soaked at 30°C. This was attributed to the degradation of the carbohydrates by the natural flora of microorganisms. Increasing the soaking temperature during natural fermentation decreased the fluid consistency index and increased the flow behavior index of the batter, demonstrating a lower viscosity and increased fluidity. All the samples revealed shear thinning behavior. Gelatinization temperature of the wheat batter decreased with increase in soaking temperature as demonstrated by viscoelastic analysis (loss modulus, storage modulus, Tan δ) of the samples.