The Study On The Extraction And Physicochemical Properties Of Dietary Fiber From Huyou Peel

Huyou is a unique citrus varities of Changshan County in Zhejiang province. After years of development, it also appears in Zhejiang, Jiangxi, Sichuan and Fujian province, and it is rich in resources and high yield. But after the Huyou eaten or processed, about50%of the peel is discarded. If the peel is not treated timely and correctly, we will not only pollute the environment, but also waste resources. Huyou peel is rich in vitamins, cellulose, mineral and active ingredient which is beneficial to human body, and has high medicinal and health care value. Dietary fiber content is very high in Huyou peel, and dietary fiber has many physiological functions as "the seventh nutrient". It plays an important role in preventing diseases and ensuring human health. Therefore, this paper aims to research the extraction process of soluble dietary fiber and insoluble dietary fiber in Huyou peel, and physicochemical properties of insoluble dietary fiber, for providing experimental basis for the development of Huyou peel dietary fiber products.In this paper, we used acid method to extract soluble dietary fiber in Huyou peel. Through single factor and orthogonal experiments, we obtained the optimum processing technology of the extraction of soluble dietary fiber:ratio of liquid to material was25:1, temperature was80℃, time was60min, pH was3. In this optimum condition, the yield of soluble dietary fiber was6.36%.We use the measure of combining enzyme and chemistry to extract insoluble dietary fiber in Huyou peel. Through the response surface method to design experimental and regression analysis method, the insoluble dietary fiber extraction conditions were optimized, we obtained the optimum process conditions:amylase content was0.4%, enzymolysis time was55min, the NaOH concentration was1.0mol/L, alkaline hydrolysis time was60min. The rate of extraction of insoluble dietary fiber was62.33%. The order of various factors on extraction of insoluble dietary fiber in Huyou peels:amylase dosage> alkaline hydrolysis time>enzymolysis time>NaOH concentration.Particle size and temperature had significant effects on the physicochemical properties of insoluble dietary fiber. pH had little effect on the physicochemical properties of dietary fiber. When insoluble dietary fiber was smashed to60mesh, their water holding capacity, swelling capacity and oil holding capacity were very high. The higher the temperature was, the higher the water holding capacity and swelling capacity were. But the oil holding increased firstly and then decreased with the increase of temperature.