Effect of different dielectric drying methods on the physic-chemical properties of a starch-water model system

Abstract

To investigate the structure and morphological characteristics of potato starch-water model starch system dried under dielectric field of different wave length (included 27, 915 and 2450MHz). The ratio of amylose/amylopectin content, molecular mass (Mw), degree of crystallinity and surface morphology were determined. The results indicated that the starch crystalline changed from type A to type B, and the crystallinity increased upon the dielectric drying. The Mw of dried starch was ranged from 1.532×107 to 2.059×107 and the ratio of higher degree of polymerization (>150) varied from 20.57% to 6.87% (27MHz), 0% (915MHz) and 0% (2450MHz). These Mw and degree of polymerization variations result..