Physiological maturity in an avocado fruit can be defined as the stage of development where most growth has occurred, while ripeness suggests a readiness for consumption. On the other hand, horticultural or "commercial" maturity can be defined as the developmental stage where harvested fruit will undergo normal ripening and provide good eating quality. The price of fruit is usually high early in the picking season, encouraging the harvest of immature fruit which do not ripen properly, but become watery, rubbery, flavorless, shriveled, and blackened. Identification of horticultural maturity is difficult for many fruit, especially avocado, because maturation is not accompanied by changes in external appearance. Moreover, mature avocado fruit do not ripen on the tree, but soften several days after being picked. Thus, it is difficult to judge in advance whether a fruit is mature enough to ripen satisfactorily. Since acceptable eating quality depends on flavor, aroma, color, and texture, a taste panel analysis of ripe fruit is the only true test of horticultural maturity. However, taste-panel testing can occur only after ripening. An objective test which is highly correlated with acceptable taste would be desirable
To maintain consumer confidence and to assist growers in developing markets for their fruit, the California Avocado Standardization Bill was signed on July 24, 1925. Under this law, "It is illegal to sell or offer for sale avocados that are immature or overripe. Avocados shall not be considered mature when the edible portion shows an oil content of less than 8% by weight by chemical analysis" (22). In avocado fruit, oil content is high enough to be measured and its increase is closely related to fruit development. However, maturity based on 8% oil has never been completely satisfactory because oil content at acceptable taste varies among cultivars.