红小豆蒸煮过程中的糊化特性及微观结构

采用质构仪、快速黏度分析仪、扫描电子显微镜、X射线衍射仪和傅里叶变换红外光谱仪等对不同蒸煮时 间的红小豆硬度、糊化特性及微观结构进行了系统研究，并对其基本组分、硬度、结晶度、糊化度以及糊化特性进 行相关性分析。结果表明，随着蒸煮时间的增加，红小豆淀粉、蛋白质含量、糊化特性、硬度以及结晶度均呈现显 著降低（P＜0.05）后又趋于平缓的趋势，糊化度变化趋势相反，脂肪无显著变化（P＞0.05）。蒸煮过程中红小豆 叶肉细胞横截面的组织结构发生明显变化，细胞间隙变大，轮廓消失，淀粉颗粒完全暴露，呈现较为光滑、规则的 椭球形颗粒。红外光谱图中表征淀粉构型敏感带的吸收峰强度减弱，指纹区的部分吸收峰减弱甚至消失，X射线衍 射、红外光谱扫描两种方法都证明了蒸煮过程中淀粉结构的变化。相关性分析表明，红小豆淀粉含量、糊化度、糊 化特性、硬度以及结晶度之间具有极显著的相关性（P＜0.01）。

Pasting Properties and Microstructure of Adzuki Beans during Cooking

The hardness, pasting properties and microstructure of adzuki beans during different cooking times were studied by using a texture analyzer, a rapid viscosity analyzer, a scanning electron microscope, X ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The correlation among basic components, hardness, crystallinity, gelatinization degree and pasting properties was also analyzed. The results showed that the contents of starch and protein, pasting properties, hardness and crystallinity showed a descending trend followed by leveling off with the increase of cooking time, while the gelatinization degree showed the opposite trend. However, there was no significant change in fat content (P < 0.05). During cooking, the cross-sectional microstructure of cotyledon cells in adzuki beans changed significantly. The starch granules were completely exposed and showed smooth and regular spherical particles as a result of wider cell gap and the disappearance of cell contour. The infrared spectra showed that cooking could decrease characteristic peak intensity in the sensitive regions, and some fingerprint regions also decreased or even disappeared. Both XRD and FTIR confirmed that structural changes of adzuki bean starch during cooking. Correlation analysis showed that starch, gelatinization degree, pasting properties, hardness and crystallinity had a very significant correlation with each other (P < 0.01).