Varietal influence on the microwave popping characteristics of sorghum

Popped sorghums are popular snack foods and are usually prepared using dry heat. In this investigation, the effect of varieties (Nandel, local Red, Mugad, GJ 42), which were having distinct physico-chemical properties and pericarp thickness on popping properties were studied. Each of the four sorghum varieties was pretreated by moisture conditioning up to 16.5 ± 0.5% wb, 0.5% salt and 10% oil, and popped by domestic microwave oven set at 900 W for 140 s. Popping and sensory properties of popped sorghum grains were measured. The physico-chemical properties such as, diameter, sphericity, thousand grain weight, particle density, bulk density, hardness, amylose content, fat, protein, carbohydrate, ash were found to be significantly different among the four varieties. Amylose content and pericarp thickness were highly positively correlated to popping yield and volume expansion ratio. The Mugad grain variety showing the highest popping qualities, found to have small grain size (3.04 mm), lower sphericity (0.99), high bulk density (833.4 kg/m3), medium grain hardness (10.55 kg), higher pericarp thickness (56.46 μm) along with higher amylose content than the other four varieties.