Variation among sorghum genotypes for reduction in popping caused by threshing-induced kernel damage

Abstract

ABSTRACT Interest has increased in pop sorghum (Sorghum bicolor (L.) Moench) as an alternative to popcorn as an ingredient in snack foods and as a confectionary snack per se. However, studies on the effect of sorghum genotype, agronomic production and grain processing on popping quality are limited and this has hindered the development of sorghum hybrids specifically for popping. This study assessed the effects of sorghum genotypes, threshing methods, environments and their interactions on sorghum popping quality. Grain from six sorghum genotypes previously documented to have good popping quality was produced in two Texas environments and was threshed using five methods which were expected to cause varying levels of kernel damage. Popping quality, measured as popping efficiency, expansion ratio and flake size was influenced primarily by threshing method, sorghum genotype and to a lesser extent by environment and the genotype × threshing method interaction. The results herein indicate that threshing methods can significantly reduce popping quality and that sorghum genotypes differ in their inclination to threshing-induced kernel damage. Based on these results, popping quality in sorghum is optimized by selecting genotypes for high popping quality and threshing the grain using a method that inflicts minimal damage to the kernel. Abbreviations: ER, Expansion Ration; FS, Flake Size; KHI, Kernel Hardness Index; PE, Popping Efficiency; TKW, Thousand Kernel Weight; UPK, Un-popped Kernels