以黏度和还原糖含量为指标,探讨了微波预处理对高浓度玉米淀粉液化的影响,并对其机理进行了分析。结果表明:经微波预处理后,高浓度玉米淀粉在糊化、液化过程中的粘度低于对照,而还原糖含量明显高于对照,为高浓度玉米淀粉的液化创造了更好的条件。其主要机理可能是:微波预处理使玉米淀粉颗粒表面变得粗糙,且出现孔洞,增加了颗粒的比表面积,同时颗粒结构变得疏松,结晶度下降,导致在升温糊化、液化过程中酶对淀粉颗粒的降解作用更加明显;另外,微波预处理也可能使部分淀粉链发生了一定程度的降解。

Using viscosity and reducing sugar contents as the indexes,the effects of microwave pretreatment on liquification of corn starch at a high concentration were investigated,and its mechanism was analyzed.The results showed that,during the gelatinization and liquificaction of high concentration corn starch,the viscosity of microwave-treated starch paste was lower and the reducing sugar content was higher than the control one.Therefore,microwave pretreatment could lead to more efficient liquification of corn starch at a high concentration.This may due to the microwave pretreatment which caused surface area rough and holey,and lower the crystallinity of corn starch granule,resulting in higher rate of starch granule degradation by enzyme during the gelatinization.In addition,microwave pretreatment could also make some starch chains break to a certain extent.