以湖北省9个品种的大米作为研究对象,通过对不同品种的大米全粉、脱脂米粉和脱蛋白米粉的物化特性进行比较,研究大米中蛋白质和脂肪对大米淀粉物化特性的影响。结果表明:不同品种大米中的基本物质含量有显著差异(P〈0.05);脱脂、脱蛋白对大米粉的透光率有较明显的影响;脂肪和蛋白质在大米中抑制了淀粉凝沉的进行,脂肪的抑制效果更明显;蛋白质对大米淀粉的膨润力、溶解度有抑制作用,脂肪对膨润力、溶解度也有小幅度的抑制作用,但没有蛋白质的作用明显;蛋白质对大米淀粉热特性的影响较大,与糊化焓变值呈负相关关系,脂肪对大米淀粉热特性影响较小,与糊化焓变值呈正相关关系;蛋白质阻碍了大米淀粉回生的过程,而脂肪对大米淀粉回生的过程没有影响;不同来源的大米脱脂、脱蛋白处理对淀粉物化特性的影响程度存在差异。
Using nine varieties of rice in Hubei province as the research object, comparing the physicochemical properties a- mong rice flour, nonfat rice flour and nonprotein rice flour, the influence of protein and lipid on the physicochemical properties of starch were studied. The results showed that: the substance contents in different varieties of rice were different significantly (P〈0.05). Deproteinization and degreasing had significant impact on the transmittance of rice flour. The existing of protein and lipid may suppress the retrogradation of starch, the inhibitory effect of lipid was more obvious. The protein had inhibitory effect on the swelling power and solubility of starch, the same as the lipid, but the inhibitory effect of lipid was not significant. The influence of protein on the thermal characteristics was larger comparing with lipid. The protein and gelatinization enthalpy value were negatively correlated, but lipid and gelatinization enthalpy values were positively correlated. The protein hindered regenerative process, but lipid had no effect on it. Deproteiniztion and degreasing had different influence on the physicochemical properties of starch of different varieties of rice.