Technique Optimization For Extracting Tenebrio Molitor Chitin By Response Surface Methodology

This research mainly according to the breeding scale of the Tenebrio molitor and the broad market prospect of chitin, in order to make full use of the resources of Tenebrio molitor, the Tenebrio molitor was used as raw material to extracted chitin. Because traditional process has many disadvantages, the whole process was improved. To Explored the optimum process conditions to extract chitin form Tenebrio molitor with organic acid and protease.The study was conducted in three phases:1. Used a variety of organic solvent to the Soxlet's extraction and the organic solvent extraction process to extracted oil, designed time gradient and times to extracted oil. Choosing organic solvent extraction method to extract oil was more suitable for mass production with analysis the rate of oil. Under the condition of using the Soxlet's extraction, petroleum ether treated5h, just only once the extraction rate could reached the highest in the laboratory.2. Used three kinds of proteases, papain?trypsin?pepsin, to do the experiment. Based on single factor of trypsin with the amount of trypsin, the time of hydrolysis and the ratio of solid to liquid, the test condition was optimized by using Box-Behnken central composite design and response surface analysis theory with17experiments, in which the center point experiment was repeated5times. It is conclusion that, under the condition of pH was8.0and temperature was40?, the trypsin need1.32%, the ratio of solid to liquid was1:25(g/mL), hydrolysis for3h, finally the content of residual protein would be4.38%±0.01%.3. Instead of hydrochloric acid, acetic acid?citric acid and malic acid were used to get rid of ash. Based on single factor of acetic acid with the concentration of acetic acid, the time and the ratio of solid to liquid, the test condition was optimized by using Box-Behnken central composite design and response surface analysis theory with17experiments, in which the center point experiment was repeated5times. It is conclusion that, the concentration of acetic acid was17%, the ratio of solid to liquid was1:43(g/mL), the time was9h, the ash of the chitin would be0.29%±0.01%and the chitin would be in the food grade.Finally, used organic acid combined with the protease under the optimum processing conditions to extract chitin from Tenebrio molitor, the extraction rate of chitin would be6.48%±0.29%, the content of protein of the chitin would be4.19%±0.18%,the ash of the chitin would be0.29%±0.01%.