【摘要】 本文利用热分析技术(TG、DSC、DMA)对小麦储藏过程中生物大分子物质的变化情况进行了探讨。TG法主要了解小麦的热稳定性,DSC法探索了小麦籽粒中大分子晶体区域的热量变化情况,测试结果表明:Tp随储藏时间的增加而增加,△H随储藏时间的增加而减少;DMA法讨论了小麦中非晶区大分子的热量变化情况,结果显示:Tg与储藏时间呈多项式的关系,相关系数为0.842;Te-To与储藏时间线性相关,相关系数0.956。通过测定Te-To,即可根据Y=-1.931X+116.5算出小麦储藏时间,进而评价其新鲜度。更多还原

【Abstract】 The change of biomacronolecule in wheat during storage was investigated by means of thermal analysis techniques, such as thermogravimetry ( TG) , differential nscaning calorimetry ( DSC) and dynamic mechanical analysis (DMA) . The thermal stability of wheat can be easily known by TG. The thermal properties of the biological polymer in wheat crystalline regions were revealed by DSC. The result showed that with the increase of wheat storage time their peak melting temperature (Tp) increased and the melting enthalpies (△H) decreased. Thermal characterization of amorphous or semi- crystalline biomaterimals in wheat were discussed by DMA. The result indicated the glass transition temperature (Tg) had amultinomial relationship with storage time(r = 0.842) ,and that the glass transition temperature range(Te - To) had a lineal relationship with storage time(r = 0.956) . The wheat freshness can be evaluated by calculation of the storage time according to the following equation: Y = -1.931X + 116.5.更多还原