环氧氯丙烷改性对小麦醇溶蛋白膜结构与性能的影响。

Influence of epichlorohydrin modification on structure and properties of wheat gliadin films.

作者信息

Song Yihu, Li Lingfang, Zheng Qiang

机构信息

Department of Polymer Science and Engineering, Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of Education, Zhejiang University, Hangzhou, China.

出版信息

J Agric Food Chem. 2009 Mar 25;57(6):2295-301. doi: 10.1021/jf802961b.

DOI:10.1021/jf802961b

PMID:19253963

Abstract

The present study was to examine influence of epichlorohydrin (ECH) modification on structure and properties of glycerol-plasticized wheat gliadin films casting from ethanol/water (70/30 v/v) solution. The modified films were characterized using proton nuclear magnetic resonance ((1)H NMR), Fourier transformation infrared (FTIR) spectra, dynamic mechanical analysis (DMA), and scanning electron microscopy (SEM). Water resistance (moisture absorption MA, water vapor permeability WVP, and weight loss in water WLW), tensile mechanical properties (Young's modulus E, tensile strength sigma(b), and elongation at break epsilon(b)), and thermal decomposition behavior were evaluated in relation to ECH content. Experimental results revealed that ECH modification gave rise to marked reduction in WLW and significant improvements in E and sigma(b), which were accompanied by slight variations in MA, WVP, and thermal decomposition temperature. The improvements of E and sigma(b) were related to the formation of a partially cross-linked protein network even though the modification led to reductions in percentages of the hydrogen bonded NH groups and the beta-sheet structure.

摘要

本研究旨在考察环氧氯丙烷（ECH）改性对由乙醇/水（70/30 v/v）溶液流延制备的甘油增塑小麦醇溶蛋白膜结构与性能的影响。采用质子核磁共振（(1)H NMR）、傅里叶变换红外（FTIR）光谱、动态力学分析（DMA）和扫描电子显微镜（SEM）对改性膜进行表征。针对ECH含量，评估了耐水性（吸湿率MA、水蒸气透过率WVP和水中失重WLW）、拉伸力学性能（杨氏模量E、拉伸强度σ(b)和断裂伸长率ε(b)）以及热分解行为。实验结果表明，ECH改性使WLW显著降低，E和σ(b)显著提高，同时MA、WVP和热分解温度略有变化。尽管改性导致氢键合NH基团和β-折叠结构的百分比降低，但E和σ(b)的提高与部分交联蛋白网络的形成有关。