Changes in the chemical composition and enzyme activity of two sapodilla (Manilkara zapota) cultivars during development and ripening

Fruits of sapodilla cvs Cricket Ball and Oblong, harvested at four developmental stages, and mature fruit latex were analysed. The principal carbohydrates identified were sucrose, glucose and fructose with a little starch. Ripe Cricket Ball fruits had more starch, fructose, protein, soluble amino acids and vitamin C, and less vitamin A, acidity and tannin than Oblong. Paper chromatographic separation of soluble amino acids indicated both qualitative and quantitative maturation pattern changes between the cultivars. Dry matter decreased until the mature stage, with a decline in alcohol-insoluble solids, starch, protein, soluble amino acids, vitamins and several minerals, and increases in soluble sugars. Carbohydrates, organic acids, amino acids, vitamins, minerals and tannins were present in the latex. Pectinesterase, catalase, peroxidase, polyphenol oxidase and adenosine trisephosphatase activity increased during ripening. Cellulase activity showed little change during development and ripening. Details are given of the techniques used.