Nondestructive methods to evaluate maturity level of oranges

The maturity on the tree and the ripening during postharvest of 2 orange varieties (Citrus sinensis, cvs. Lanelate and Valencia) were evaluated, using 3 methods: the ratio soluble solids/titratable acidity (Maturity Index); the firmness, by hand densimeter, and the skin color with a portable colorimeter, The values of Color Index (1000a*/L*b*) and firmness complement each other for defining the maturity of tree fruit. Color and Maturity Indices are not correlated with time or weight losses during storage (8 degrees C) or with shelf life (20 degrees C). Firmness and weight loss are significantly (P less than or equal to 0.05) correlated with each other, and both of them independently of each other, with postharvest time.