大米淀粉晶体/非晶体结构耐热性研究

Study on Heat Resistance of Rice Starch Crystal/Amorphous Structure

采用中红外(MIR)光谱及二维中红外(2D-MIR)光谱分别开展大米结构及其淀粉晶体/非晶体结构热变性研究。实验发现:大米的红外吸收模式主要包括:νOH-大米、νas CH2-大米、νs CH2-大米、νamide-Ⅰ-大米、νamide-Ⅱ-大米和νC-O-大米。随着测定温度升高(303~393 K),不同产地的大米淀粉晶体/非晶体结构对于热的敏感程度及变化快慢顺序均存在一定的差异性。进一步探究相关机理,认为不同大米淀粉晶体/非晶体结构耐热性存在一定差异性,因而进一步影响其口感。并拓展了MIR光谱及2D-MIR光谱技术在大米结构及其淀粉晶体/非晶体结构热变性的研究范围。

The thermal denaturation of rice structure and its starch crystalline/amorphous structure was studied by mid-infrared(MIR)spectroscopy and two-dimensional mid-infrared(2D-MIR)spectroscopy.The results indicated that the infrared absorption modes of rice starch includedνOH-rice,νasCH2-rice,νsCH2-rice,νamide-Ⅰ-rice,νamide-Ⅱ-rice andνC-O-rice.As the measurement temperature increased(303-393 K),the sensitivity of rice starch crystals/amorphous structures to heat and the order of change were different from those in different origins.Further research on the relevant mechanism shows that there are some differences in heat resistance of different rice starch crystal/amorphous structure,which further affects its taste.The study expanded the scope of research on the thermal denaturation of rice structure and its starch crystals/amorphous structures using MIR spectroscopy and 2D-MIR spectroscopy.