Effect of Ammonium Bicarbonate on Extrusion Behaviour of Rice and Corn Grits

The effects of incorporating ammonium bicarbonate (NH4HC03) at 0, 004, 0.8, 1.2, 1.6% levels on expansion and functional properties of corn and rice extrudates were studied using single-screw extruder. Water absorption index (WAl) and viscosity office and com extrudates inereased with the increase in level of NH4HC03. WAI of rice extrudates was significantly greater than com extrudates. Viscosity of rice extrudate pastes was significantly greater than those of corn extrudates containing same levels of NH4HC03. WSI and expansion of both com and rice extrudates decreased with the increase in NH~HC03. Expansion and WSI of com extrudates was significantly higher than rice extrudates containing same levels of NH4HC03.