Physicochemical Properties of Defatted Nonwaxy and Waxy Rice Starches

탈지한 멥쌀과 찹쌀 전분의 이화학적 특성

  • Kim, Soo-Kyung (Department of Food and Nutrition, Chonnam National University) ;
  • Shin, Mal-Shick (Department of Food and Nutrition, Chonnam National University)
  • 김수경 (전남대학교 가정대학 식품영양학과) ;
  • 신말식 (전남대학교 가정대학 식품영양학과)
  • Published : 1992.08.01

Abstract

Physicochemical properties of native and defatted nonwaxy(Dongjin byeo) and waxy(Sinseunchalbyeo) rice starches were investigated. The granule shapes of rice starches were polygonal and X-ray diffraction patterns were A types, but relative crystallinity was decreased by defatting. The amylose content of defatted starches slightly increased, but water binding capacity of defatted starches decreased. Swelling power and solubility of starches increased with the increase of temperature, at each temperature increased by defatting. Transmittance of Dongjinbyeo and Sinseunchalbyeo starch suspensions showed a rapid increase at $60{\sim}65^{\circ}C$, $55{\sim}60^{\circ}C$ respectively. The initial pasting temperature by amylograph of Dongjinbyeo and Sinseunchalbyeo starches were $66^{\circ}C$ and $64^{\circ}C$, respectively. The gelatinization temperature of defatted starches was higher than that of the nondefatted starches. Dongjinbyeo starch decreased peak viscosity and breakdown by defatting, but Sinseunchalbyeo starch unchanged.

Keywords

nonwaxy and waxy rice starches;defatting;amylograph;physicochemical property