Black soldier fly as a New chitin source: Extraction, purification and molecular/structural characterization

Black Soldier Fly (BSF) represents a potential chitin source that has not been fully explored in terms of characterization, extraction, and purification. In this study, different chemical and enzymatic protocols with or without pre-treatment (ultrasonication and mechanochemical milling) for chitin extraction were tested. Chitin was then accurately quantified and characterized from a molecular and structural point of view by UPLC-MS, XRD, and ESEM, and compared with chitin from shrimp shells. BSF chitin was more recalcitrant than shrimp chitin during extraction and purification, due to the strong binding of chitin to proteins. Indeed, the purity of shrimp chitin was 88.3g/100g of extract, while BSF chitin purity was 47.6-79.9g/100g. Furthermore, the chitin bound proteins had a defined amino acid composition; their binding was also confirmed by structural characterization. Therefore, the efficiency of each step of the extraction process needs to be critically evaluated to adapt the methods used for crustaceans to insect biomass.