Study On Aqueous Enzymatic Extraction Of Cottonseed Oil And Protein

Using cottonseeds as raw material, alcohol as extraction agents, this researchsystematically studied the aqueous enzymatic extraction and the functional properties ofcottonseed oil and protein. The test results will provide the basic data for the industrialdesigning.Due to gossypol, which is a limit on the use of cottonseed products, this papermakes the technology of extraction in the condition of normal temperature and acid, andthe extraction agent is0.1wt%citric acid and90v%ethanol mixed solution. Theextraction process is maintaining3hours, and the pH value of the extraction agent is5.0,and the temperature is60℃, and the solid-liquid ratio is1:4. The whole process can getthe ethanol extract with0.61%FG and0.18%BG, meanwhile the wet cotton solid with0.025%FG. This step provides excellent raw materials for the subsequent experiment.In this process aqueous enzymatic method is used for extraction, with cellulase ascatalytic agent. Through single factor and orthogonal experiments, extraction of oil andprotein from cottonseeds are studied. Some influence factors on the extraction ratio ofthe oil are discussed. These factors involved the enzyme dosage, the ratio of cottonseedand extraction solvent, time and temperature. The optimal conditions of extraction areshowed as following: the ratio of material weight (g) to raw solvent volume (mL)1:10,the extracting time3hours, temperature55℃, enzyme dosage0.5‰, under theconditions, the extraction rate could be high as64.53%.This experiment obtain finished product of cottonseed oil with different methodssuch as adding product oil, changing the temperature and stirring. These ways can beused to refine the crude oil. This paper also researches the properties of the cottonseedoil, and conduct the test to confirm the following properties: the Lovibond colour Y35R8.0, the acid value0.8mg/g, the iodine value109g/100g, peroxide value6.0mmol/kg, the saponification value195mg KOH/g. The results are corresponded to normsof cottonseed oil in national standard.The crude extract of the cottonseed protein is sublimated tentatively bymicrofiltration membrane, and the microfiltration membrane can eliminate effectivelythe suspended particles, cellulose and other impurities in solution, letting cottonseedprotein through. The experiment is carried out in the condition of normal temperatureand the0.2MPa-operating pressure. With the circulation of operation of membrane, thefiltrate is clear and transparent. The filtrate of the microfiltration membrane isconcentrated by the ultrafiltration membrane in the condition of normal temperature andthe1.5MPa-operating pressure. The retention rate of cottonseed protein is100%and theconcentration ratio can reach10times. The hydrochloric acid is addicted by drops to filtrate until the pH reaches4.9. The cottonseed protein can be obtained and the yield isas high as90.58%after procedures of precipitation and freeze drying.