玉米植酸改性淀粉的工艺研究

Technical Study on Acid Modified Starch of Corn

为了研究植酸改性淀粉的最佳制备工艺条件,以植酸钠为改性剂,对玉米淀粉进行酯化改性。通过单因素试验,以取代度为指标,探讨p H值、反应时间、反应温度、植酸钠的用量和淀粉乳浓度等因素对植酸淀粉酯取代度大小的影响。在单因素试验的基础上,筛选出对植酸淀粉酯取代度影响显著的3个因素,并利用响应面分析法对这些因素进行优化。试验结果表明,植酸淀粉酯的最佳制备工艺条件为:植酸钠用量为2.1%,p H值7.2,淀粉乳质量分数为31.7%,50℃下反应5 h,此条件下改性淀粉的取代度为0.005 8。对植酸淀粉酯进行理化性质检验,其冻融稳定性、透明度、黏度、溶解度及膨润力相较原淀粉均有明显的提高。

In order to study the best preparation technology condition of acid modified starch, sodium phytate was used as a modifier for esterification and modification of corn starch. Through single factor experiment and takingsubstitution degree as the indicator, we discussed the effects of pH value, reaction time, reaction temperature, dos- age of sodium phytate and starch milk concentration on the substitution degree size of phytic acid starch ester. On the basis of single factor experiment, 3 factors which had the most significant effect on the substitution degree size of phytic acid starch ester were screened out, and then the method of response surface analysis were used to optimize these factors. Experimental results showed that the optimum preparation conditions of phytic acid starch ester were as follows, dosage of sodium phytate being 2.1%, pH value being 7.2, starch milk concentration being 31.7 %, the reaction time under 50 ~C being 5 h, and under this condition the substitution degree of modified starch being 0. 005 8. After checking the physical and chemical properties test of phytic acid starch ester, we found that the freeze -thaw stability, transparency, viscosity, solubility and swelling degrees were significantly improved compared with the original starch.