Study On The Preparation And Functional Characteristics Of Dietary Fiber Of Wine Grape

This paper was prepared from the by-product,and the preparation process and characteristics of Water soluble dietary fiber（SDF）and Insoluble dietary fiber（IDF）.With SDF as the main raw material,the antioxidant and in vitro glucose lowering functions of SDF prepared by two different methods,and water-coated oil emulsion were prepared with two SDF as raw materials to explore its structural characteristics and chemical composition,and initially explore its emulsification stability.The following:Dietary fiber was prepared by acid extraction method,and the optimal process conditions were:liquid ratio is 1:23,p H 1.6,extraction temperature is 85℃,and extraction time was 2 h,and the predicted value of SDF was 6.123%.The actual yield rate of SDF extracted under this condition was 6.15%,not significantly different from the predicted value.The detection results of the two conventional components of dietary fiber are:the main component of SDF is sugars such as pectin,while the main component of IDF is cellulose.Through hydration properties and the adsorption of fatty acids and cholesterol in vitro,the hydraulic force of SDF was 19.71 g/g,swelling,21.40 m L/g,12.63 g/g,6.97 g/g higher than IDF,1.00 m L/g,5.95 g/g,SDF and IDF adsorption of 1.42 and 2.27 g/g,respectively;1.58 and 1.74 g/g,respectively.Two water-soluble dietary fibers were prepared by thermal acid and enzyme methods,respectively.The functional component content of the two dietary fibers and their solubility,gelarity,vesicular and thickening were compared.SDF1 contained0.53%polyphenols,6.06%total flavonoids,and 5.64%colorin;SDF2 contained0.33%polyphenols,2.35%total flavonoids,and 8.05%colorside.Their antioxidant capacity and hypoglycemic function in vitro were also evaluated according to the effect of DPPH,ABTS,potassium ferocyanide reduction force and the inhibitory mechanism ofα-amylase andα-glucosidase.The results showed that SDF2 has better antioxidant capacity than SDF1,but the opposite in vitro glucose reduction.The physical ochemical composition content of the two water-soluble dietary fibers as well as the methylation,acetylation and molecular weight size were compared,and the infrared spectroscopy assisted analysis of composition differences due to group changes.The emulsification stability was studied by showing the Span value and the average particle size D_4,3value.The results showed that the protein content,galacturonic acid,neutral sugar,esterification and acetylation of SDF2 were lower than SDF1.Among them,the particle size change of the SDF1 sample emulsion under different conditions is low temperature（1.10～4.29μm）>room temperature（1.10～5.72μm）>high temperature（1.10 to 7.57μm）;The particle size change of the SDF2 sample emulsion was low temperature（3.73 to 17.7μm）<room temperature（3.73 to 15.30μm）<high temperature（3.73 to 12.47μm）;The overall stability of the SDF2 sample emulsion was poor;The Span value of the SDF1 sample emulsion was（3.37 to 4.18μm）>SDF2（2.84 to 3.52μm）,Therefore,the emulsion of SDF2samples is better than SDF1.