稻谷湿热处理对稻米和米粉性质影响的研究

Research on effect of paddy treated by moisture heat on the properties of rice and rice flour

通过对稻谷进行湿热处理,测定处理前后稻米膨胀率和直链淀粉含量变化,并对处理前后的米粉进行品质特性测定。研究发现:湿热处理前后,稻米蒸煮膨胀率由20.00%上升至34.00%;直链淀粉和不溶性直链淀粉含量变化显著,直链淀粉含量由21.26%上升到25.3%,不溶性直链淀粉含量由9.96%上升到13.09%;RVA测定米粉糊化峰值黏度由299RVU降为97RVU,物性分析仪测量黏度由70.62下降到35.74,凝胶的弹性、硬度都有显著变化,硬度由60.414 g上升到117.783 g,弹性由0.88上升到0.91。试验结果表明,处理后稻米的直链淀粉含量与淀粉质构性和黏滞性的相关性达显著水平,同时不溶性直链淀粉的含量增加也影响稻米的品质特性。

Paddy was prepared by moisture heat treatment,the changes of quality properties of rice and its flour were determined before and after the treatment.The result showed that the swell rate of rice increased from 20.00% to 34.00%,the contents of amylose and insoluble amylose increased significantly,from 21.26% to 25.3% and 9.96% to 13.09%,respectively.The gelatinization peak viscosity of rice flour decreased from 299 RVU to 97 RVU determined by Rapid Viscosity Analyzer（RVA）.The adhesiveness of rice flour decreased from 70.62 to 35.74 determined by Texture Analyzer.The hardness and springiness of rice flour also changed observably,from 60.414g to 117.783g and from 0.88 to 0.91,respectively.The results indicated that after moisture heat treatment the amylose content of rice starch was significantly correlative with the viscosity property and texture property,the contents of insoluble amylose could also influence the quality properties of rice.