Extraction Of Fat And Concentration Of Polyunsaturated Fatty Acids In Dendrolimus Punctatus Walker

Dendrolimus punctatus Walker is one kind of serious forestry insect pests in our country. However, it is also a beneficent biology resource with potential development value from the aspect of nutrition. The oil extraction, physic-chemical properties of oil, concentrating poly-unsaturated fatty acids from the larva of D. punctatus were studied in this dissertation.This paper studied the influence of solvent, the percentage of insect powder and solvent, extraction temperature and time on gross fat of Dendrolimus punctatus Walker. It also used orthogonal-experiment design to improve extraction methodology of gross fat. The result showed that the better extraction solvent, percentage of insect powder and solvent, extraction temperature and time were as follows:petroleum ether,1:10,30℃,2h. The extraction percentage of gross fat was 93.30% under this extraction condition.The oil value of iodine, acids, peroxidation, specific gravity and saponification of the pupae of Dendorlimus punctatus Walker were 125.67 gI2/100g,1.59 mg/g, 10.34meq/kg,0.9137g/g,163.48mg/g, respectively. The results of concentration of polyunsaturated fatty acids with low temperature crystallization showed that time and temperature of low temperature of crystallization had obvious influence on the concentration of polyunsaturated fatty acids. The better concentration condition of temperature and time was as the follows:crystallization temperature was -8℃, crystallization time was 18h, the iodine value and peroxidation value under this condition were 230.01 gI2/100g,61.75%, respectively.The concentration of polyunsaturated fatty acids of Dendorlimus punctatus Walker with the method of urea complexation showed that factors of quality percentage of fatty acid and urea, time and temperature of crystallization had obvious influence on the concentration of polyunsaturated fatty acids of it. The better urea complexation condition were:quality percentage of fatty acid and urea was 1:6, crystallization time was 12h, crystallization temperature was 0℃, the iodine value and peroxidation value under this condition was 261.32gI2/100g,50.41% respectively under this condition.This was the first dissertation which made systematically study on the extraction of oil, the physic-chemical properties and concentration of Dendorlimus punctatus Walker in our country. The results obtained in the dissertation would be useful for the further study and development of functional foods and other products related to Dendrolimus punctatus Walker.