Germinated melon seed flours: physical and physicochemical characteristics, bioactive compounds and technological properties

The exploitation of fruit residues is a tendency that has been raising considerable interest, since it reduces the amount of residues generated during agro-industrial processing, increases the profit generated in the operation and makes use of nutritional principals normally disposed of. Melon seeds are good sources of macronutrients such as proteins, lipids and carbohydrates, as well as micronutrients such as vitamins, minerals and bioactive compounds. The germination process leads to a modification in composition, possibly increasing the nutritional quality and altering the physicochemical characteristics of the original raw material positively. Thus, the aim of the present study was to make a comparative evaluation of the physical and physicochemical characteristics, the bioactive compound content and the technological properties of flours produced from the germinated seeds of Pele-de-Sapo, Gália, Cantaloupe and Orange melons, obtained after drying at 50, 60 and 70 ºC. The germinated seed flours of the four melon varieties presented good protein, lipid, ascorbic acid, flavonoid and carotenoid contents, especially Cantaloupe, with the best values for proteins, lipids and carotenoids and the highest phenolic compound contents. All the flours were highly cohesive with low fluidity and good solubility. The variety Cantaloupe provided flours with good water and oil absorption capacities and greater emulsion activities and stability. The highest drying temperatures led to increases in the phenolic compound, flavonoid and carotenoid compounds and increased the Hausner Factor and Carr Index, but reduced the solubility, the water and oil absorption capacities and the emulsion activity. The flours produced showed good nutritional quality and stability, with emphasis on those produced from Cantaloupe melons, which showed the best nutritional characteristics and technological properties.