压热-酶法制备碎米抗性淀粉的工艺及其结构特性研究

Enzymatic Pressure-heating Preparation of Broken Rice Resistant Starch and its Structural Properties

研究以碎米为原料压热-酶法制备抗性淀粉的工艺。通过单因素和正交试验,获取最佳工艺条件:淀粉浆质量浓度20%、压热温度125℃、压热时间40min、普鲁兰酶添加量3.5U/g干淀粉、酶解时间6h。在此条件下碎米抗性淀粉得率为16.8%;采用扫描电镜观察分析表明碎米抗性淀粉具有更稳定的晶体结构,具有抗酶解性;运用X-射线衍射图谱分析其结晶性,发现原碎米淀粉为A型,而碎米抗性淀粉的结晶结构为B、V型结合体,表明抗性淀粉是难消化的。

Enzymatic pressure-heating preparation of broken rice resistant starch was studied and optimized through single factors and orthogonal tests as follows： 20 g/mL of starch slurry concentration, 125℃ of autoclaving temperature, 40 rain of holding time, 3.5 U pullulanase per gram of dry starch and 6 h of enzymolysis. Yield of resistance starch was 16.8% under these conditions. Scanning electron microscope observation indicated that the broken rice resistant starch had the stable crystal structure with anti-enzymolysis property. X-ray diffraction of its crystallinity showed that broken rice starch was of A type, while the broken rice resistant starch＇s crystallization structure was of the coalition of B and V types. Those indicated that the resistant starch was the stodginess.