Nutritional and Bioactive Profiling of Cucumis melo L. By-Products: Towards a Circular Food Economy

Food waste, due to the high quantities produced, becomes a significant environmental, economic, and social challenge worldwide. Simultaneously, the rising prevalence of chronic diseases has intensified the demand for healthier food options. A promising approach to address these issues involves the valorisation of food by-products for the development of innovative and healthier food products. Cucumis melo L., commonly consumed as a fruit, generates peels and seeds that are typically discarded. In the present study, the nutritional composition and antioxidant potential of pulp, peel, and seeds of C. melo L. (yellow and green melon) were comprehensively evaluated. The seeds were identified as a rich source of dietary fibre (39.0 and 39.7 g/100 g dw; p > 0.05) and protein (21.0 and 21.3 g/100 g dw; p > 0.05), exhibiting an appealing fatty acid profile. The peel contains high levels of dietary fibre (39.7 and 47.1 g/100 g dw; p > 0.05) and total phenolic compounds (1976 and 2212 mg GAE/100 g dw; p > 0.05), suggesting significant bioactive potential. The peels showed a high antioxidant capacity for both methods used, DPPH• (120 and 144 mg TE/100 g dw; p > 0.05) and FRAP (6146 and 7408 mg TE/100 g dw; p > 0.05) assays. Potassium emerged as the predominant mineral in the seeds (799 and 805 mg/100 dw; p > 0.05), while glutamic acid was the most abundant amino acid (4161 and 4327 mg/100 g dw; p > 0.05). These findings emphasise the antioxidant and nutritional properties of C. melo L. by-products, highlighting their potential for inclusion in novel food formulations. This study not only advances the understanding of C. melo L. properties but also supports the reduction of food waste and promotes sustainability within the food supply chain.