Starch Properties of a Waxy Mutant Line of Hull‐less Barley (Hordeum vulgare L.)

Endosperm starch isolated from an amylose-free waxy mutant hull-less barley line, Shikoku Hadaka 97, had an amylose content of 0.3% and higher swelling power than ordinary waxy barley cultivars/lines with amylose contents of 2.2-6.5%. A highly significant correlation was observed between amylose content and swelling power among waxy barley starches. No clear differences were detected in the chain-length distribution profiles or thermal properties between the amylose-free starch and ordinary waxy starch. The chain-length distribution profile of waxy barley starch was slightly different from that of normal barley starch. Gelatinization temperatures and gelatinization enthalpy of waxy barley starch were higher than those of normal barley starch. Significant correlations were observed between amylose content and thermal properties of starch samples analyzed. Waxy barley starch stained with a concentrated iodine-potassium iodide solution showed a ghost-like appearance.