New Sweetpotato Lines have High Amylose and Resistant Starch Contents

Abstract

The sweetpotato is an important starch crop and a health‐promoting food, owing to its richness in functional components. New sweetpotato lines (HA lines) with high amylose and high resistant starch (RS) contents are developed by cross‐breeding, and the authors evaluate the root and starch properties and the influence of heat‐treatment on the RS contents of these HA lines. The HA lines are found to have comparable root weights; much lower starch contents; more than 28% higher (45–59%) amylose contents; much lower viscosities, gelatinization temperatures, and gelatinization enthalpy changes; a higher proportion of both amylose and short chains (DP 6–11) fractions in the unit chain distribution of the debranched starches; and higher RS contents in gelatinized starches, raw, and heat‐treated roots than those of the ordinary varieties. These results present useful information for food industries and breeders of sweetpotato.