酸解醋酸酯复合变性大米淀粉的研制

酸解醋酸酯复合变性大米淀粉的研制(6100字)
摘  要：本文以大米淀粉为原料，以盐酸为酸解剂，醋酸酐为乙酰化试剂，氢氧化钠为酰化催化剂制备酸解乙酰基复合变性淀粉。考察了反应时间、反应温度、pH值、酸含量对酸解淀粉酸解程度及糊透明度、乙酰化淀粉取代度的影响。试验结果表明：升高酸解温度、增加酸解时间和酸含量将加速淀粉的降解，增加醋酸酐含量提高淀粉取代度而pH及时间达到峰值后反而抑制乙酰化反应。
关键词：酸解；乙酰化；复合变性淀粉；大米淀粉

Studies on preparation of acid-thinned and esterified rice starch
Abstract：The preparation and properties of acetylated acid hydrolysis modified starch by using rice starch as raw materials,hydrochloric acid as acid hydrolysis reagent,acetic anhydride as acetylation reagent and sodium hydroxide as catalyst,were introduced in this paper.The effect of some factors such as acid hydrolysis time,acid hydrolysis temperature,concentration of hydrochloric acid and pH on viscocity,transparency and substitution degree of modified starch was discussed.The results showed that the increase of acid hydrolysis temperature,time and concentration of hydrochloric acid speeds the starch hydrolysis. To increase the contents of acid anhydride speeds up the replacing degree,it will depress acetylation reaction after the acetylation temperature and pH reached their peak.