Qunyu Gao
South China University of Technology, China
Title: Preparation and physicochemical characteristics of sweet potato resistant starch under heat-moisture treatment
Biography
Biography: Qunyu Gao
Abstract
Sweet potato starch was subjected to cross-linking to achieve high content of resistant starch (RS) under heat-moisture treatment and the physicochemical properties of cross-linked sweet potato starches were investigated. A maximum RS content (72.45%) was obtained after 10% STMP/STPP (99/1% w/w) at 120℃ and pH 11.5 with a 20% moisture level. Through the analysis of 31P nuclear magnetic resonance (31P NMR) spectroscopy, the RS-72.45% contained distarch monophosphate (DSMP), not be detected monostarch monophosphate (MSMP). After cross-linking, the starches with high moisture treatment (≥25%) were observed loss of birefringence and surface erosion. The X-ray diffraction patterns showed unchanged in crystal type but with slightly alteration in the relative crystallinity of cross-linked starches. The gelatinization temperature increased as the moisture content increased, while gelatinization enthalpy apparently decreased.