What's beyond macro- and micro-nutrients? NMR metabolite profiling of edible insects for a larger view of their features

Introduction: Edible insects are becoming even more a nutritional source and a valid protein alternative to the conventional ones, with attention being mainly focused on main macro- and micro-nutrients. Anyway, these matrices are also a rich source of other metabolites involved in other properties different from nutritional one, namely biological and organoleptic. In this context, NMR metabolomics is here proposed and innovative approach on edible insects to obtain a more complete view of their chemical profile and properties.

Materials and methods: NMR metabolomics was applied on different edible insect species (A. domesticus, T. molitor, L. migratoria) considered at different conditions (rearing, drying, growth stage) to define their metabolite composition. Mono- and two-dimensional experiments were carried out on both polar and apolar extracts to identify as many metabolites as possible.

Results and discussion: The obtained results allowed to observe a profile characterized by metabolites belonging to different classes (amino acids, sugars, organic acids, nitrogenous compounds, etc.) and involved in nutritional but also organoleptic and biological properties. These data further underline the potential properties and applications of edible insects as alternative food sources. Moreover, it was observed that the metabolite profile is strictly correlated with any production variable applied on the samples, underlining how NMR metabolomics can be a potential tool to monitor production processes or any other variable that can affect edible insect composition and properties.

Conclusion: The value of edible insects as innovative food sources was further valorized in this study, since NMR metabolomics allowed to identify compounds previously never detected in these matrices. The obtained results showed that, together with conventional analyses of macro- and micro-nutrients, metabolite profiling is an added value in defining nutritional and other properties of edible insects.