Protein quality and physical characteristics of Kisra (fermented sorghum pancake-like flatbread) made from tannin and non-tannin sorghum cultivars

Abstract

Kisra is a naturally lactic acid bacteria- and yeast-fermented sorghum thin pancake-like flatbread produced in Sudan. Kisra has considerable potential as the basis for development of a gluten-free sandwich wrap. To help direct cultivar selection for commercial production of these products, two white, tan plant non-tannin Type I, one white Type II tannin, and one red Type III tannin sorghum cultivars were evaluated with respect to kisra protein quality and physical characteristics. Kisra from the non-tannin sorghums were flexible and had an open-textured structure with many regular gas cells, whereas those from the tannin sorghums were more brittle, denser in structure, and contained far fewer and smaller gas cells. Kisra from the tannin sorghums had the lowest reactive lysine content, in vitro protein digestibility, and Protein Digestibility Corrected Amino Score (PDCAAS), with values being lowest for the Type III sorghum. PDCAAS of kisra from the Type III sorghum was only 0.12, less than half of that from the Type I sorghums. As the tannins in tannin sorghums adversely affect kisra protein quality and physical characteristics, white tan plant, non-tannin sorghum cultivars are most suitable for kisra production and for development of wrap-type sorghum-based baked goods.