Strategic Advances in Efficient Chitin Extraction from Black Soldier Fly Puparia: Uncovering the Potential for Direct Chitosan Production

As a biodegradable material, chitin possesses exceptional physical and chemical properties, making it valuable in various industrial sectors. Compared to chitin, its derivative, chitosan, offers even more versatile applications due to its higher solubility and reactivity. As the key precursor for chitosan production, chitin is typically harvested from shrimp and crab exoskeletons. However, the quest for alternative sources has intensified to reduce reliance on crustacean-derived chitin. Black soldier fly (BSF, Hermetia illucens), particularly its puparium, has emerged as a promising alternative, though it is typically considered waste. In this study, we investigated different combinations and sequences of extraction treatments for chitin from the BSF puparium. The results demonstrate that sequential treatments of demineralization (DM), deproteination (DP), and decolorization (DC) produce chitin with the lowest ash, lipid, and protein contents—approximately 1.01%, 1.99%, and 3.01%, respectively, yielding degrees of DM and DP at 94.77% and 92.24%, and a chitin purity of 93.98%. In contrast, combining DP and DC following the DM treatment facilitates partial chitosan transformation with a degree of deacetylation (DD) of 65.90%, offering a direct alternative for producing chitosan without an additional deacetylation process.