Studies On The Preparation Process Of Maggot Oil, Protein Powder And Chitin

Maggots, which were the larvae of Calliphoridae Lucilia sericata (Lucilia), Chrysomyia megacephala or other closely related insect larvae, were also known as maggot, Shuixian Ko and Chinese traditional herbal medicines. Because of its richment in fat, protein, fatty acids and other nutrients and medicinal ingredients, in recent years it has become a research hotspot. In this study,we focused on the preparation of its oil, protein powder and chitin.After drying of the larvae body, the oil of larvae was extracted using the subcritical fluid extraction (butane) method. Single factor experiment selected level of response surface optimization experiment showed that the significant factors affecting the extraction were volume ratio, time and temperature. In extraction temperature of 37 ℃, extraction time of 45 minutes, volume ratio of 0.13, the extraction rate was 19.21%. The iodine value, saponification value and acid value of maggot oil were 96.5 ± 0.21gI/100g,178.1 ± 0.22mgKOH/100g and 9.5 ± 0.15mg KOH/g, respectively. GC-MS analysis showed that 23 kinds of fatty acids were detected and the unsaturated fatty acid content were higher than 70.78±0.05%, with oleic acid and linoleic acid as the main compounds. Unsaturated essential fatty acids of linoleic acid, which can not be synthesized by human body, was more than 14%.Defatted maggot was further used to extraction its proteins. Results showed that the best extraction condition was alkali extraction pH11-12, extraction temperature 40 ℃, and material-water ratio of 1:2. When pH value was adjusted to 7.0, most of the protein was precipitated and the protein recovery was 81.74%. Protein solution was further desalted by ultra-filtration membrane systems and the desalination of 54.33% obtained with protein concentrate of 4.4 times. Protein powder was prepared by spray drying and more than 10% of glutamic acid, proline and arginine in the composition was detected.Finally, chitin was prepared by high temperature and low alkali technology, after single factor experiment, the best extraction condition of solution temperature 118 ℃, extraction time 105min and 4.5% of the alkali concentration obtained. The residue of inorganic salts and protein in the product were 1.71% and 2.0%, respectively. Infrared spectra of chitin showed that its infrared spectral features conform to the features of chitin.In this study, we obtained the simple and efficient methods to comprehensive utilization of maggots, this will benefit to further utilization of insect resource.