Publications

Detailed Information

Retrogradation of amylosucrase treated waxy corn starch by temperature cycling: structural and digestibility properties : 아밀로수크레이스 처리 후 온도 사이클링으로 노화시킨 찰 옥수수 녹말의 구조 및 소화 특성

Cited 0 time in Web of Science Cited 0 time in Scopus
Authors

남새미

Advisor
문태화
Major
농업생명과학대학 농생명공학부
Issue Date
2014-08
Publisher
서울대학교 대학원
Keywords
amylosucrasewaxy corn starchretrogradationtemperature cyclingin vitro digestibilitystructural properties
Description
학위논문 (석사)-- 서울대학교 대학원 : 농생명공학부, 2014. 8. 문태화.
Abstract
In this study, waxy corn starch was treated by amylosucrase (AS), followed by retrogradation under different temperature cycles or isothermal storage. Various retrogradation conditions were used to accelerate crystallization of amylopectin chains elongated by AS: temperature cycling with a low temperature of 4 °C for 1 day and a high temperature of 20, 40, or 60 °C for 1 day for 3 or 7 cycles, and isothermal storage at 4 °C for 6 days or 14 days. The properties of AS-treated starches were determined by high-performance anion-exchange chromatography and the iodine binding capacity (IBC). The properties of retrograded starches were determined by X-ray diffractometry, differential scanning calorimetry, 13C CP/MAS NMR spectroscopy, and in vitro digestibility.
After the AS treatment, the proportion of short chains (DP ≤ 12 and DP 13-24) decreased, whereas that of long chains (DP 25-36 and DP ≥ 37) increased. Also, IBC was similar with that of normal corn starch. Following the retrogradation for 14 days, the X-ray diffraction patterns of all AS-treated starches showed a B-type polymorph. In the control starches, compared to starches stored only at 4 °C, the starches stored under the temperature cycles exhibited lower relative crystallinity and melting enthalpy due to the melting of unstable crystallites during storage at higher temperatures. Little difference in ordered structure content was observed. On the other hand, the AS-treated starches stored under the temperature cycles exhibited higher relative crystallinity, melting enthalpy, ordered structure content, and resistant starch content than the isothermal storage at 4 °C. Among all starches, the AS-treated starch retrograded under 4/60 °C cycled condition particularly showed the most striking changes in structural and digestibility properties.
Conclusively, this study demonstrated that temperature cycling could induce reassociation of elongated chains by AS treatment and accelerate retrogradation. It also suggested that retrogradation by temperature cycling brought more changes in structural and digestibility properties of AS-treated starch than control starch.
Language
Korean
URI
https://hdl.handle.net/10371/125863
Files in This Item:
Appears in Collections:

Altmetrics

Item View & Download Count

  • mendeley

Items in S-Space are protected by copyright, with all rights reserved, unless otherwise indicated.

Share