Influence of microwave parameters and water activity on radical generation in rice starch

卷:196

Fan, Daming ; Liu, Yixiao ; Hu, Bo ; Lin, Lufen ; Huang, Luelue ; Wang, Liyun ; Zhao, Jianxin ; Zhang, Hao ; Chen, Wei

Jiangnan Univ

关键词: Electron paramagnetic resonance;    Raman spectroscopy;    Carbohydrate radicals;    Rice starch;    Microwave activation;   

DOI  :  10.1016/j.foodchem.2015.09.012

学科分类：食品科学和技术

【 摘 要 】

Radical generation in rice starch under microwave treatment as well as the related chemical bond changes were investigated by electron paramagnetic resonance (EPR) and Raman spectroscopy. Samples with water activity of 0.4 and 0.7 have been treated and analyzed. It was found that microwave power level and water content could influence the amount of radicals along with the radical components and their contribution. Raman spectra showed corresponding changes in vibrational features of chemical bonds. During storage the signal intensity started to drop after a short period of increase. Rice starch radicals were relatively stable and could exist a long time in room temperature. Through signal simulation, 3 main components were separated from the original spectra and the evolving process was investigated. The main component was the radical located on Cl position in the glucose ring. (C) 2015 Published by Elsevier Ltd.