Structural Characteristics of Kidney Bean Starch

강낭콩 전분의 분자구조적 특성

  • Kim, Kwan (Department of Food Science and Technology, Chunnam National University) ;
  • Kang, Kil-Jin (Department of Food Science and Technology, Chunnam National University) ;
  • Kim, Sung-Kon (Department of Food Science and Nutrition, Dankook University)
  • 김관 (전남대학교 식품공학과 및 농업과학기술연구소) ;
  • 강길진 (전남대학교 식품공학과 및 농업과학기술연구소) ;
  • 김성곤 (단국대학교 식품영양학과)
  • Published : 1996.06.30

Abstract

Some structural characteristics of kidney bean starches (3 varieties : Pink kidney bean, Red kidney bean and White kidney bean) were investigated. The amylose content and the ${\beta}$-amylolysis limit of kidney bean starches were $32.6{\sim}34.5%$ and $69.9{\sim}71.0%$, respectively. The kidney bean amylopectin was composed of super long chain of ${\overline{DP}}$ above 60 ($5.28{\sim}12.62%$), B chain of ${\overline{DP}}$ $45{\sim}60\;(29.85{\sim}33.65%)$ and A chain of ${\overline{DP}}\;10{\sim}20(22.94{\sim}29.85%).$ The chain distribution of kidney bean starches were different from variety to variety. The acid (2.2 NHCI) hydrolysis of kidney bean starches showed, as hydrolysis time increased, the patterns of three stages. The acid hydrolysis rate and iodine reaction of acid treated starches were different from variety to variety As acid hydrolysis time increased, the amylose and the ${\alpha}$-1.6-glucosidic linkage of amylopectin of amorphous state were gradually hydrolyzed. Finally, the chain of ${\overline{DP}}$ 20 of crystalline state was left in the acid treated starches.

Keywords

kidney bean;starch;molecular structure;acid treatment;chain distribution;amylopectin;amylose