Enzymatic approach to improve the nutritional and functional feature of Tenebrio molitor

With a growing world population, increasingly demanding consumers, and a limited amount of agricultural land, finding new alternative protein sources is one of the most interesting goals for human and animal nutrition and health. The edible insects and their derivatives perfectly fit in this framework as an alternative protein source for humans. As most protein-containing foods, insects can also induce IgE-mediated allergic reactions in sensitive human and, although further investigation are needed, the process used to prepare the ingredient might affect the composition and bioavailability of protein thus modulating the effect on humans. The present project aimed at optimizing a bio-technological protocol by using an enzymatic cocktail (Flavourzyme ® and Alcalase®) for the enhancement of the nutritional (protein digestibility, amino acids and peptides concentration and profile) and functional (bioactive compounds) features of Tenebrio molitor flour. Both culture-depended and - independent approaches (NGS, new generation sequencing) have been used to define the insect microbiota. An integrated approach, including chromatographic and electrophoresis analysis have highlighted the role of the enzymatic treatment in the improvement of peptide (up to 600 mg/g) and free amino acids (up to 140 mg/g) concentration as well as the in-vitro protein digestibility (20% higher than untreated flour) and antifungal activity (up to 66%). To understand the role of the enzymatic treatment on the degradation of protein responsible for the IgE-mediated response, extracts of the enzymatically treated flour (during treatment) have been applied on volunteers (with and without shellfish allergy) skin. The insect flour prior and after 3 and 6 h of enzymatic treatment has been used to fortify bread which, according to Regulation CE n.1924/2006, can be considered as “source” and with “high content” of proteins and are characterized by improved nutritional indices