荞麦壳水不溶性膳食纤维提取工艺的优化

Optimization of extracting water insoluble dietary fiber from buckwheat shell

【目的】确定化学浸提法提取荞麦壳水不溶性膳食纤维的最佳工艺参数,为合理利用荞麦壳资源提供参考依据。【方法】采用化学浸提法对荞麦壳水不溶性膳食纤维进行提取,探讨料液比、碱解时间、碱解温度和NaOH浓度对水不溶性膳食纤维提取率的影响,并采用正交试验设计优化提取工艺。【结果】NaOH浓度对水不溶性膳食纤维提取的影响最大,其次是碱解温度和碱解时间,料液比影响最小;化学浸提法提取荞麦壳水不溶性膳食纤维的最佳工艺条件为:料液比1.0∶15.5,碱解时间60min,碱解温度45℃,NaOH浓度4%。从荞麦壳中提取的水不溶性膳食纤维持水力300.25g/g,膨胀力5.57mL/g,色泽为焦黄色,可用作食品添加剂。【结论】化学浸提法能有效提取出荞麦壳水不溶性膳食纤维,且方法简单、可控、耗时短,适用于工厂化大规模生产,但必须控制好NaOH浓度。

[Objective]Using chemical extraction, optimal technological parameters for water insoluble dietary fiber were determined to provide references for rationally utilization of buckwheat shell resources. [Method]Water insoluble dietary fiber was extracted from buckwheat shell by chemical extraction method. Effects of liquid-solid ratio, reaction time and temperature, and NaOH concentration ten extraction rate of water insoluble dietary fiber were studied and the extraction technology was optimized using an orthogonal experiment. [Result]The sequence of affecting extraction rate was like this： NaOH concentration〉reaction time and temperature〉liquid-solid ratio. The optimal technological parameters for chemical extraction of water insoluble dietary fiber were as follows： liquid-solid ratio 1.0：15.5, reaction time of 60 min, reaction temperature 45℃, NaOH concentration 4%. [Conclusion]Under above-mentioned optimal extraction conditions, the water insoluble dietary fiber extracted from buckwheat shell was toast tan with water-holding capacity of 300.25 g/g and expansibility of 5.57 mL/g , which could be used as food additives.