Study On Extraction Of High Active Tea Insoluble Dietary Fiber And Its Function

Tea residuemain byproduct of the tea processing industry.The objiective of this paper is to use the tea residue as raw material,based on the analysis results of main component in the tea residue, insoluble dietary fiber extraction technology with chemical method mainly using acid, alkali and ether in stages was studied,and then bleaching technology was rescerched using H2O2. In the end, the physiological function of the tea insoluble dietary fiber was rescerched by means of the simulation in vitro and the mice gastrointestinal function experiment.The results showed that the type of acid had no significant effect while pH value had a significant effect for insoluble dietary fiber extraction. After investigated the single factor influencing regularities of the pH and temperature of HC1 solution and extraction time on extraction insoluble dietary fiber, an optimized HC1 hydrolyzation conditions with Lg(34) orthogonal experiment are pH value 1, temperature 90℃and time 2h, in this case, the insoluble dietary fiber purity in the obtained initial product is 31.27%, yield is 58.30%. Then the initial product hydrolyzed with NaOH solution. Based on the influencing regularities of single factor and comparison the purities of the insoluble dietary fiber before and after de-fat, optimized NaOH extraction conditions are pH value 13.5, temperature 90℃and time 3h. The intermediate product obtained on the optimized conditions has 85.25%insoluble dietary fiber, yield is 21.47.The intermediate producfurther degreesed by aether, a last product has 91.32%insoluble dietary fiber, yield is 20.11%.To improve the color and the quality of the tea insoluble dietary fiber, it studied on bleaching technology of insoluble dietary fiber using H2O2. The research studied on the influences of H2O2 concentration,NaOH concentration,reaction time and temperature on bleaching effect on the tea insoluble dietary fiber based on the single factor experiment, determined the optimum conditions of the bleaching technics by the uniform design experiments. The result shows that the primary-secondary factors effect on the bleaching technics is H2O2 concentration>NaOH concentration> bleaching time>reaction emperature;the optimum conditions are 5.5%of H2O2 concentration,1.2% of NaOH concentration,45℃of reaction temperature and bleaching for 3.5 hours. Under these conditions,the whiteness of tea insoluble dietary fiber is 76.62 after bleaching. Comparing the activation effect of tea insoluble dietary fiber after bleaching, the results showed that the expansive capacity and water holding capacity of the insoluble dietary fiber was increased by 96%-172%,3.47-4.27ml/g.Tea insoluble dietary fiber (IDF) was used as raw material. Based on the simulation in vitro and the mice gastrointestinal function experiment, it studied the expansive capacity and the water holding capacity of IDF in the manual simulation circumstance, and the effect of IDF on the mice gastrointestinal function. The result showed that:The expansive capacity and water holding capacity of IDF had no difference in different manual simulation circumstance. The expansive capacity and water holding capacity of different mesh IDF was different in the manual simulation circumstance, among which, the 80 mesh IDF had the higher expansive capacity and water holding capacity than others. The gastrointestinal function of different mesh IDF had obvious difference, the function of 60 mesh IDF was not significant; the 80 mesh IDF had obvious relieving constipation function,but had no intestinal peristalsis promotion function; the 100,150'and 200 mesh IDF can significantly relieving constipation and promote intestinal peristalsis.