摘要
通过碱处理籼米粉(蛋白含量为7.85%)分离得到蛋白含量分别为2.36%,4.23%,0.38%的籼米淀粉、黄淀粉和白淀粉,并对3种淀粉的糊化与结构特性进行研究。RVA分析结果表明,籼米粉的糊化峰值粘度、热糊粘度和最终粘度均极显著低于籼米淀粉、黄淀粉与白淀粉(P<0.01),与DSC对样品糊化温度的分析结果一致;RVA分析发现籼米淀粉和黄淀粉的粘度值没有显著差异(P>0.05),而DSC结果表明黄淀粉和白淀粉的糊化温度最为接近。对样品的结构进行分析发现:碱处理籼米粉后3种淀粉的透光率均降低;平均链长白淀粉最长、籼米粉最短,聚合度白淀粉最大、籼米粉最小,黄淀粉和籼米淀粉的聚合度和直、支链淀粉的链长接近;蛋白亚基籼米粉和籼米淀粉主要含60,33,22,13ku亚基,黄淀粉主要含60,22,13ku亚基,白淀粉中主要含60,33ku亚基。显微结构分析发现不同的淀粉中,存在少量的蛋白质和纤维素。说明淀粉以外,蛋白质的含量与组成及其与纤维素的相互作用对籼米粉的糊化特性也有一定的影响。
The rice starch（RS）,yellow starch（YS）and white starch（WS）,which protein content were 2.36%,4.23%,0.38% respectively,were obtained after indica rice flour（protein content was7.85%）treated by alkaline,and their pasting and structure properties were then studied.Results of RVA indicated that the peak viscosity,hot pasting viscosity and final viscosity of rice flour had significantly lower than rice starch,yellow starch and white starch（P〈0.01）,which agree with the result of the pasting temperature tested by DSC;RVA analysis also found that the viscosity between rice starch and yellow starch had no significant effect（P〈0.05）,while DSC result believed that the pasting temperature were approached between yellow starch and white starch.The structure analysis of the samples showed that transparency decreased with indica rice treated by alkali;the WS of average chain length was longest,while rice flour shortest;and as well the polymerization degree.To protein subunit,there were 60 ku,33ku,22 ku and 13 ku mainly in rice flour and RS;60ku,22 ku and 13 ku maily in YS,60 ku,with33ku in WS.The results of microstructure showed that the interaction of protein or protein with fiber was different.This study demonstrated that,beside starch,the pasting property of indica rice flour was also affected by the content and composite of protein,and interaction of protein with fiber.
出处
《食品与机械》
CSCD
北大核心
2016年第4期5-8,51,共5页
Food and Machinery
基金
国家自然科学基金资助项目(编号:31301404)
关键词
大米蛋白
籼米
淀粉
糊化特性
结构
rice protein
indica rice flour
starch
pasting properties
structure
