Chemical changes during the development and ripening of the fruit of Cucumis melo (cv Makdimon)

Changes in the aroma volatiles, free amino acids, sugars, principal acids, and soluble minerals were studied during the development and ripening of the fruit of Cucumis melo L. Reticulatis group cv. Makdimon. Ethyl acetate was the most abundant volatile produced during the final growth stage, but ethanol was the major volatile found in immature fruit. Most of the free amino acids exhibited increases in concentration as the fruit underwent the ripening process. Sucrose, although absent in immature fruit, showed a dramatic increase during ripening to become the major carbohydrate constituent in the ripe fruit. The changes in total soluble solids during ripening showed close correlation with those found for pH, certain amino acids, and the elements sodium and potassium. Sucrose concentration has been shown to be an important fruit quality indicator, so these further correlations suggest that some of these parameters may be significant additional determinants of eating quality.