Resistant starch content among several sorghum (Sorghum bicolor) genotypes and the effect of heat treatment on resistant starch retention in two genotypes

• There is significant variability in the resistant starch levels in sorghum genotypes.
• Some sorghum genotypes can be considered resistant starch sources.
• Wet heat caused a drastic reduction in the resistant starch levels in sorghum.
• Dry heat caused small decreases in the resistant starch levels in sorghum.

The resistant starch (RS) contents in 49 sorghum genotypes and the effects of heat treatment using dry and wet heat on the grain and flour from two sorghum genotypes were investigated. The results showed a wide variation in the RS contents of the genotypes analyzed. The RS mean values were grouped into six distinct groups and ranged from 0.31 ± 0.33 g/100 g to 65.66 ± 5.46 g/100 g sorghum flour on dry basis. Dry heat causes minor losses in the RS content with retentions of up to 97.19 ± 1.92% of this compound, whereas wet heat retained at most 6.98 ± 0.43% of the RS. The SC 59 and (SSN76)FC6608 RED KAFIR BAZINE (ASA N23) cultivars, which have an average RS content of 65.51 g/100 g, were appropriate for human consumption, and the use of dry heat is presented as a better alternative for the preservation of RS in heat-treated grains.