山楂水溶性膳食纤维提取工艺及结构研究

Study on Extraction Process and Structural Properties of Water Soluble Dietary Fiber from Hawthorn

为开发山楂中的活性功效,研究提取山楂水溶性膳食纤维的影响因素及最佳工艺参数,采用正交试验对山楂水溶性膳食纤维超声波辅助提取工艺进行优化。以山楂水溶性膳食纤维得率为指标,对超声功率、pH值、超声时间、酶添加量进行试验研究。试验结果表明:最佳工艺为超声功率320 W、pH4.4、超声时间11 min、加酶量0.5%,并在最佳工艺的条件下山楂水溶性膳食纤维的得率达到了6.12%,其纯度为91.63%。山楂水溶性膳食纤维通过电镜扫描呈现葡萄状;通过粒径分析其颗粒分布集中,且平均粒径为19.5μm;通过X-衍射分析可以得出其结晶度为13.45%;通过红外分析表明山楂水溶性膳食纤维在3 450 cm^(-1)～2 900 cm^(-1)、2 900 cm^(-1)～2 800 cm^(-1)、1 647 cm^(-1)均有吸收峰,直接印证了其含有羟基、糖类亚甲基、糖醛酸等基团。

In order to develop the active efficacy in hawthorn,the influencing factors and optimal process parameters of extracting hawthorn water-soluble dietary fiber were studied.The optimum extraction conditions of water soluble dietary fiber from hawthorn were determined by single factor test and orthogonal test.The factors order was ultrasonic power,pH,ultrasonic time,amount of added enzyme.The test results showed that the optimal process was ultrasonic power 320 W,pH 4.4,ultrasonic time 11 min and enzyme dosage 0.5%.Under these conditions its yield reached 6.12%and its purity was 91.63%.Scanning by electron microscopy revealed that the water-soluble dietary fiber of hawthorn was grape-like;The particle size distribution was concentrated by particle size analysis,and the average particle diameter was 19.5μm;X-ray diffraction analysis could be found that the crystallinity was 13.45%;Infrared analysis showed that the water-soluble dietary fiber of hawthorn had absorption peaks at 3 450 cm^-1-2 900 cm^-1,2 900 cm^-1-2 800 cm^-1 and 1 647 cm^-1 and it was described as containing a hydroxyl group,a saccharide methylene group,a uronic acid group or the like.