超声-微波辅助酶法对小米SDF提取和物理性质的影响

目的为了提高小米中水溶性膳食纤维(SDF)的得率,实验采用超声-微波(U-M)辅助酶法提取小米SDF,并对提取工艺进行优化。方法以小米SDF的得率为测定指标,对微波功率、提取温度、提取时间、料液比等4个因素进行单因素试验,并利用正交试验对以上4个因素进行优化。对此条件下提取的SDF和采用传统酶法提取的SDF得率及其物理性质进行研究。结果得到了提取小米粉SDF的最优条件,微波功率为550 W,料液比(g/mL)为1:25,微波温度为55℃,微波时间为20 min,提取率为13.63%,比传统酶法提取的SDF含量提高了46.88%;通过对小米SDF物理性质的测定,发现超声-微波处理对小米SDF的持水力、膨胀力、持油力均有显著提高,分别提高了24.79%,25.16%,15.74%。结论通过超声-微波辅助酶法可以提高小米SDF的得率,对其物理性质影响显著。

Influence of Ultrasonic-microwave Assisted Enzymatic Method on Extraction and Physical Properties of Water-soluble Dietary Fiber from Millet

The work aims to extract the millet SDF in the ultrasound-microwave(U-M)assisted enzymatic method during the experiment and optimize the extraction process,in order to improve the yield of water-soluble dietary fiber(SDF)in millet.According to the yield of millet SDF,microwave power,extraction temperature,extraction time and material-to-liquid ratio were tested by single factor,and the above-mentioned four factors were optimized by orthogonal test.The yield and physical properties of SDF extracted under this condition and conventionally extracted SDF were studied.The optimum conditions for extracting SDF from millet flour were:550 W microwave power,1∶25 material-to-liquid ratio,55℃ microwave temperature,20 min microwave time and 13.63% extraction rate,which was 46.88% higher than that of traditional enzymatic extraction.By measuring the physical properties of millet SDF,it was found that the ultrasonic-microwave treatment significantly improved the water holding capacity,swelling power and oil holding capacity of millet SDF,which increased by 24.79%,25.16% and 15.74%,respectively.Ultrasound-microwave assisted enzymatic method can improve the yield of millet SDF and has a significant effect on its physical properties.