魔芋葡甘聚糖羧甲基化方法改进研究  

Improvement of the preparation method for carboxy methylation of konjac glucomannan

作　　者：汪超[1] 李斌[1] 谢笔钧[1] 陈君仙[1] 

机构地区：[1]华中农业大学食品科技学院,武汉430070

出　　处：《农业工程学报》2005年第5期140-144,共5页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家高技术研究发展计划(863计划)(批准号:2002AA2Z4181)

摘　　要：针对魔芋葡甘聚糖(KGM)分子结构特性进行羧甲基化方法的改进,在乙醇介质中先混合醚化试剂,再进行碱化催化反应制备羧甲基魔芋葡甘聚糖(CMK)。通过单因素和正交试验,对其改性反应条件进行优化,以取代度(DS)和表观黏度(η)为评价指标,综合二者确定羧甲基化的最佳条件为:55℃、pH12反应3.0h。产物DS可高达0.5278,最大η为15.57Pa·s。同时,运用红外光谱分析对KGM羧甲基化反应历程进行了探讨,所得CMK溶胀速率快,水溶胶透光率高。The improved preparation method for carboxy methylation of konjac glucomannan (KGM) was proposed in this paper according to molecular structural characteristics of KGM. Carboxymethyl konjac glucomannan (CMK) was prepared by blending konjac glucomannan with etherification agent firstly and then basifying and catalyzing in ethanol. Through single factor and orthogonal experiments, the effects of reaction conditions on degree of substitution (DS) and apparent viscosity (η) were investigated, and the optimum reaction conditions were obtained as follows: 55°C, pH 12 for 3 hours. The results indicate that the maximal values of DS and η were 0.5278 and 15.57 Pa·s, respectively. The reaction mechanism for carboxy methylation of KGM was proposed and checked by infrared spectra. Meanwhile, it also shows that the properties of CMK are rather good in terms of hydrated rate and hydrosol transmittance.

关 键 词：魔芋葡甘聚糖 羧甲基化 红外光谱 溶胀速率 透光率 

分 类 号：S632[农业科学—蔬菜学] TS201.7[农业科学—园艺学]