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The Dendrolimus punctatus is one of the country's major forestry pests, but from the the resources science point of view, it also is a class of biological resources that can be exploited. Chitin is nature, in addition to cellulose the most abundant natural polymer, chitosan, chitin deacetylase. Of chitin / chitosan versatile, has in many areas in the application of chitin / chitosan home and abroad, the demand will continue to expand. Thesis Dendrolimus punctatus larvae as raw materials, mainly pH Act (preparation the dilute acid demineralization dilute alkali deproteinizing, hydrogen peroxide bleaching and concentrated alkali deacetylation), the extraction process of chitin and chitosan. process. Chitin extraction process using a single factor test, respectively, the concentration of sodium hydroxide, the concentration of sodium hydroxide soak time deproteinized soaking temperature and sodium hydroxide and hydrochloric acid, hydrochloric acid soak time and hydrochloric acid soaking temperature demineralization results show that: (1) sodium hydroxide, the higher the concentration, the longer the soaking time, the higher the temperature of the soaking, deproteinized better; the higher the concentration of hydrochloric acid (2) The soaking time is longer, the higher the soaking temperature the demineralization better. From the economic viewpoint, the combination of product quality and indicators to determine the optimal process: the sodium hydroxide concentration is 8%, the treatment temperature was 80 ° C, the processing time was 12h; hydrochloric acid in a concentration of 3%, the treatment temperature was 40 ℃ treatment time of 8h. This condition, white or light yellow flake solid chitin. The extraction of the product was 8.46%, and a moisture content of 7.85% -8.89%, ash content of less than 1%, a nitrogen content of 6.28% -6.84%. The obtained chitin quality index is equal to or higher than the standard of industrial-grade chitin. Chitosan three factors and three levels of orthogonal experiment, three factors were NaOH concentration, soaking time and soaking temperature. Concentration of NaOH and soaking time on the degree of deacetylation significant variance analysis. The best process is obtained by the orthogonal experiment: NaOH concentration of 35%, soaking time of 10h, soaking temperature of 30 ° C. In this condition, until flaky white or slightly yellow solid chitosan. The resultant product a moisture content of 7.67% -9.35%, an ash content of 0.76% -1%, deacetylation degree of 91.58% -94.30%, a viscosity of 18.7-20.7Mpa · s. The resulting product quality indicators close to or higher than the standards of industrial grade chitosan. Extraction, an important step in the preparation of chitin / chitosan process - bleaching process research. The results showed that the optimum conditions for decolorization: soaking temperature of 40 ° C under the conditions, select hydrogen peroxide as a bleaching agent, bleaching agent concentration of 10%, soaking time for 3h to Tuotuo color. The decolorizing agent selection and soaking temperature on decolorization effect was most significant. The obtained chitosan is white or light yellow flaky solid, some slightly pearl luster, moisture 6.5% -8.76% 0.89% -1% ash, 91.45% -93.46% degree of deacetylation, viscosity 19.8-20.47mPa · s. Dendrolimus punctatus larvae of extraction of chitin, chitosan and chitin / chitosan decolorization process for the first time, at home and abroad in this regard yet reported. The experimental results with dendrolimi future development of functional foods and other products with some guidance.
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