Study On The Physicochemical Properties And Characteristics Of Citrus Fruit Dietary Fiber

The dietary fiber (DF) is beneficial to human body and soluble dietary fiber (SDF) content of citrus fruits is very rich. With the continuous changes in the diet, the intake of dietary fiber is seriously insufficient, and the increase of all kinds of nutritional diseases is caused.Therefore, the development and utilization of citrus DF has become one of the hot issues of current research. In the present study, ten cultivars were collected, representing six citrus species.The objective of this work is to characterize dietary fiber of citrus fruit for effective and reasonable utilization of citrus fruit, and provide theoretical basis for development of new types of dietary fiber resources. The main results are described as follows:Dietary fiber were extracted from citrus fruit as experimental materials, found that the average content of cellulose, hemicellulose, lignin and pectin of dietary fiber were41.49%,15.22%,22.40%and20.77%, respectively, and the average value of swelling capacity, water holding capacity, oil holding capacity and glucose absorption capactiy were10.32ml/g,4.82g/g,1.95g/g and0.87mmol/g, respectively.Characterization of10varieties of citrus fruit dietary fiber was studied. SEM morphology observation found dietary fiber powder evenly distributed; using a laser particle size analyzer to analyze the particle size of dietary fiber;studies on its monosaccharide composition, found that dietary fiber of citrus fruit is mainly composed of glucose, galacturonic acid, galactose, xylose, arabinose, glucuronic acid and rhamnose, and its average concentration is56.31%,20.28%,10.39%,4.60%,3.68%,2.68%and2.05%; IR spectra show it has the typical carbohydrate absorption peaks C=O bond, OH bond, COOR and free of·O-H, single sugar components for the structure is of a pyran ring structure, there uronic acid and carboxylic acid dimer. Crystallinity of the highest and lowest dietary fiber were lemon and Satsuma; citrus fruit dietary fiber heating process can be divided into three stages, phase I starting temperature of25℃, the termination temperature of125-146℃, phase Ⅱ starting temperature of266-274℃. the termination temperature of341-373℃, the starting temperature phase Ⅲ is342-378℃, the termination temperature of427-520℃, and in phase Ⅱ thermal decomposition is obvious.