羧甲基化法制备高持水力麦麸膳食纤维研究

Research on the Preparation of High Water-Holding Capacity of Dietary Fiber from Wheat Bran through Carboxymethylation

以不溶性麦麸膳食纤维为原料,持水力为指标,对羧甲基化法制备高持水力麦麸膳食纤维进行了研究。根据单因素试验结果,利用响应面对碱化时间、乙醇体积分数、反应温度和反应时间进行了优化,确定羧甲基化改性麦麸膳食纤维的最佳工艺条件为氢氧化钠浓度为3.38 mol/L,碱化温度35℃,碱化时间56min,乙醇体积分数87%,醚化温度53℃,醚化时间3.3 h,在此条件下改性产品的得率为113.87%,改性产品的取代度为0.293 9;产品持水力为11.825 g/g,与改性前相比,产品持水力提高了105.79%。

This article has studied the high water - holding capacity of dietary fiber from wheat bran through the Carboxymethylation method. It uses insoluble dietary fiber from wheat bran as raw materials and waterholding capacity as its index. According to results of single factor experiment,response surface methodology（RSM） is used to optimize four factors which are alkalization time, ethanol concentration, reaction temperature and time. And it has determined that the optimum conditions of Carboxymethylation to improve the dietary fiber from wheat bran are as follows ： the con- centration of NaOH is 3.38 mol/L; alkalization temperature is 35 ~C ; reaction time is 56 min ; the ethanol concentra- tion is 87% ; the etherifieation temperature is 53 ~C and the etherifieation time is 3.3 h. On this condition,the rate of modification products is 113.87%, and the substitution degree of modification products is 0.293 9. Compared with the raw material,the water- holding capacity of modified sample is 11. 825 z/z.which has raised bv 105.79%.