Production of carotenoid-rich Hermetia illucens larvae using specific agri-food by-products

Nowadays, the mass production of insects is promoted not only for their nutritional value, but also for their ability to convert agri-food by-products into high valuable derived products. In the present work, the potential production of carotenoid-rich larvae of black soldier fly, Hermetia illucens (BSFL), was evaluated by rearing them on different agri-food by-products. The carotenoid concentration in BSFL was highly correlated with the carotenoid content of the substrates (R=0.882). Among the different substrates, tomato and carrot by-products allowed to obtain BSFL with a total carotenoid content 230% higher than the amount detected in the BSFL grown in the control diet. Furthermore, the killing method played a key role in the preservation of the BSFL carotenoid content, with dry heating resulting in a significantly higher total carotenoid content compared to blanching and freezing. These results clearly support the valorisation of agri-food by-products for the production of BSFL naturally rich in carotenoids for specific feed and food purposes.