【摘要】 以小麦淀粉为原料,用耐高温α-淀粉酶液化可制备异麦芽低聚糖。采用正交试验法,对小麦淀粉液化过程的影响因素进行了研究。研究结果表明,最佳工艺条件为pH值5.6～5.8,淀粉乳质量分数25%,温度85℃,SPEZYMEFred用量14LU/g,液化时间80min,所得液化液的DE值为15.62。用原子力显微镜研究了淀粉液化前以及液化后DE值分别为7～9和11～13时液化淀粉的拓扑结构,得到了淀粉在液化过程中颗粒结构变化的直接图像证据。它表明随着液化程度的提高,淀粉的颗粒逐渐被破坏,由粒状变为枝状。这些图像也是淀粉中存在粒状结构、直链结构和支链结构的直接证据。更多还原

【Abstract】 Using wheat starch as raw material,and thermostable α-amylase SPEZYME Fred as liquefacient,isomalto-oligosaccharide was prepared.The factors which affected liquefying of wheat starch were investigated by orthogonal tests.The results showed that the optimum condition was as follows:pH value was 5.6～5.8,the mass percent of starch pulp was 25%,liquefying temperature was 85℃,the usage quantity of SPEZYME Fred was 14 LU/g,liquefying time was 80 minutes.On this condition,DE value of liquefied solution was 15.62%.The topology nanostructure of starch pulp was researched by atomic force microscopy when the wheat starch was not liquefied and DE value of liquefied starch pulp was 7～9 and 11～13.Image evidence of starch granules’ structure change was obtained.With the increase of liquefied degree,Starch granules were broken up gradually and became branch structure.These images proved that starch granules were composed of particle structures,amylose structures and amylopectin structures.更多还原