GC-MS-Based Metabolomics for Understanding the Metabolite Profile of Mopane Worm (Gonimbrasia belina) and Sorghum (Sorghum bicolor L).

Edible insects are nutritious, having high levels of protein, essential amino acids, healthy fats, vitamins, and minerals. In areas where sorghum is a primary crop, mixing this gluten-free grain with protein-rich insect powder provides a novel approach to making nutrient-rich products. Understanding the sorghum and mopane worm flours' metabolomic changes during bioprocessing can however, enhance their nutritional value and food safety. The research investigated metabolite compounds that are found in raw and processed (fermented, malted (sorghum), and ultrasonicated) mopane worms and sorghum. In the study, sorghum grains were traditionally fermented and malted at 35°C for 48 h and ultrasonicated for 10 min, at 70 Hz amplitude, while mopane worm was also traditionally fermented at 35°C for 48 h and ultrasonicated for 10 min at 70 Hz amplitudes. Obtained results showed that samples contained 67 (mopane worm) and 49 (sorghum) metabolites, which demonstrated distinct metabolic fingerprints for raw versus processed samples. The notable differences were found in lysine, threonine, and valine between the ultrasonicated sample and other treatments, while linoleic acid was the dominating compound in the ultrasonicated samples. Scyllo-inositol was the primary sugar, while lactic acid and citric acid were notable in the fermented samples. The ultrasonicated mopane worm flour had more metabolites identified than raw and fermented samples while in sorghum, the fermented sorghum had more metabolites than raw, malted, and ultrasonicated ones. These findings provide insights into optimizing processing techniques to maintain or improve the nutritional quality of both the investigated samples.