Process optimization for hot air puffing of barnyard millet (Echinochloa frumentacea)

Abstract

Hot air puffing system developed is simple, quick and easy to handle. Since the process for hot air puffing of millet grains involved heat treatments, it is necessary to verify the changes occurring during hot air puffing of barnyard millet. Millet is becoming more and more important in a time of rapidly urbanizing populations, shifting lifestyles, convenience, and, most importantly, health consciousness. People are starting to value ready-to-eat (RTE) foods for their convenience. For hot air puffing of barnyard millet, the optimum condition of process variables such as puffing temperature (PT) 310.0 °C, feed rate (FR) 7500.0 g/h, were found and the corresponding optimized quality process parameters were found to be final moisture content (FMC), expansion ratio (ER), puffing percentage (PP), whiteness index (WI), hardness (HD), and crispness (CSP) to be 4.808% db, 2.272, 72.61%, 59.04, 37.66 kg and 75.986 +ve peaks, respectively in the first pass. The unpuffed grains collected together and subjected to second pass of puffing, the unpuffed grains reduced to the tune of 0.81% from 28.39% that was found in first pass. Thus 99.19% of total barnyard millet grains were puffed, giving 72.40% of total sample weight as puffed grain and 26.79% of total sample weight as separate.