Extraction Of The Grapefruit Skin Water-soluble And Study On The Composite Film

The grapefruit polysaccharide is from the grapefruit skin slag. As a naturalpolysaccharide, it is completely biodegradable, and it is the environment friendlymaterials. In recent years, the extraction of polysaccharide and the use of polysaccharideto make film packaging material are paid more and more attention by people. In thispaper, the extraction technology, purification and application of the grapefruitpolysaccharide was investigated. The composite film with polyvinyl alcohol (pva) andthe polysaccharide was made, and the filming process was also studied.In the experiment, water-soluble polysaccharide was isolated from grapefruit withthe method of water-dissolving and ethanol-precipitating. By single factor test todetermine parameters for range of extraction technology of polysaccharide and thendesign the orthogonal experiment. Study the effect order of influence factors on theextraction of polysaccharide to determine the optimum extraction conditions. Theextraction conditions of the water-soluble polysaccharide were investigated, whichcontained solid-liquid ratio, temperature, time and pH. The results showed that pH wasthe most important factor of polysaccharide extraction, followed by temperature. Theoptimized extraction technology conditions were obtained. The solid-liquid ratio was40:1, temperature was90℃, time was2.0h, and pH was2. The highest extraction rateof crude polysaccharide was8.30%.In the experiment, the grapefruit skin polysaccharide and polyvinyl alcohol werethe main film-forming compositions. Add different proportions of additives such asglycerol, glyoxal, citric acid, and make a composite thin film by casting, and test onvarious properties of thin film. The results indicated that the polysaccharide andpolyvinyl alcohol showed better compatibility. The composite film showed good tensileproperties and fracture elongation. The maximum tensile strength reached23.2Mpa andthe maximum fracture elongation was870.3%. Under those conditions, microstructureof the composite film was good, and oil resistance was also good. And water resistancehad been improved. All laid the foundation for the application of the composite filmwith polysaccharide and PVA.