水分含量对大米淀粉糊化和回生的影响

Effects of Water Content on the Gelatinization and Retrogradation of Rice Starch

用差示扫描量热仪和动态流变仪对不同水分含量的大米淀粉糊化、短期回生和长期回生特性进行了研究。试验结果表明 :水分含量越低 ,大米淀粉越难糊化。水分含量低于 5 0 %时 ,常压下难以使大米淀粉完全糊化。对于大米淀粉的短期回生 ,水分含量越低 ,短期回生速度越慢 ,淀粉凝胶达到稳定的时间越长。对于大米淀粉的长期回生 ,水分含量 6 0 %时 ,大米支链淀粉最易重结晶 ,淀粉体系长期回生速度最快。直链 -脂类复合物的解体温度随着水分含量的降低而升高。

The effects of different water content on the gelatinization, short-term and long-term retrogradation of rice starch were studied. The experiment results indicated that rice starch with low water content was difficult to gelatinize, however rice starch with water content less than 50%could not be gelatinized entirely by normal pressure. When water content decreased, the rate of short-term retrogradation was declined, and the time for gel stabilization extended. Amylopectin was re-crystallized the most easily with a water content of 60%.The disassociation temperature of amylose-lipid advanced with low water content.