硬脂酸-羧甲基魔芋葡甘聚糖酯的微波法制备工艺及其性能研究

摘要

魔芋葡甘聚糖通过微波加热引入亲水的羧甲基基团及疏水的硬脂酸基团进行复合改性,从而改善其理化性质,扩大其应用范围.采用单因素试验研究硬脂酸甲脂及氢氧化钠的用量、微波反应时间和温度对硬脂酸-羧甲基魔芋葡甘聚糖酯取代度的影响,在此基础上通过四元二次通用旋转组合设计确定最佳工艺参数并研究所得产物的理化性质.得出最佳改性条件:硬脂酸甲脂用量在14.0%～14.4%,NaOH用量5.85%～6.36%,反应温度85.9～87.5℃,反应时间10.1～10.4 min条件下,硬脂酸取代度在0.020以上有95%的可能;相比羧甲基魔芋葡甘聚糖,产品的黏度有所提高,抗碱性能力增强,乳化能力提高且稳定,是一种优良的乳化剂.%In order to improve the physic-chemical properties of Konjac glucomannan and extend its application field, konjac glucomannan was modified with hydrophilic carboxymethyl group and hydrophobic stearate group by microwave.The effects of the amounts of the methyl stearate, sodium hydroxide, microwave reaction time, and the temperature on the degree of substitution (DS) were studied by single factor experiments.Based on these studies, the optimum reaction parameters of preparing SCMK were obtained by revolving orthogonal combinatorial design experiment,and its physical-chemical properties were investigated.The results showed that the amount of the methyl stearate, the amount of the sodium hydroxide, reaction temperature and time were about 14.0％ ～ 14.4％ , 5.85％ ～6.36％,85.9 ～ 87.5℃ and 10.1 ～ 10.4min, respectively.The percentage of SCMK with DS value of 0.020 was more than 95％.Compared with the carboxymethyl konjac glucomannan, the viscosity of the SCMK increased, the ability of anti-alkaline and emulsifying capacity and its stability improved.SCMK is a better emulsifier.