Maturity Programs

Fruit-growing regions throughout the world vary in the type and extent of maturity programs. For apples, IEC measurements and the starch index have become the most widely used maturity indices, although for some bicolored apples, e.g., 'Gala', 'Braeburn', and 'Fuji', background color is considered an important harvest index. In some cases, state regulations have been established to set minimum harvest maturities, e.g., the starch index for 'Granny Smith' in California. Currently in Washington State, individual packinghouses conduct their own maturity programs in line with their marketing strategies. In Michigan and New York, a wide range of maturity and quality indices is collected, and the optimum harvest period, sometimes called the harvest window, is established each year for major cultivars (Beaudry, Schwallier, and Lennington, 1993; Blanpied and Silsby, 1992). The Streif index is used in some parts of Europe.

Programs for stone fruit are typically less formalized. There are no established maturity programs for cherries in Washington, for example, with harvest decisions being based on fruit color, market pressure, and predicted weather. Fruit bound for Asia are harvested slightly less mature than fruit sold within the United States. For peaches, nectarines, and plums, individual companies in growing regions such as South Africa, California, Chile, and Argentina accumulate data relating to harvest maturity and subsequent eating quality, arrival condition in markets, and market life.

Irrespective of the crop involved, fruit maturity is a critical factor in consumer satisfaction and impacts the effect of the many abuses that can occur during subsequent handling operations. While certain maturity indices are more important than others in establishing the correct time to harvest fruit, the maturation and ripening processes involve many simultaneous biochemical and physiological changes. The strength of any maturity program probably lies, not in reliance on absolute maturity indices, but in discussion with industry personnel on changes in maturity and quality that are occurring over the harvest period. Commercial factors such as color, susceptibility to bruising with progressing maturity, and issues such as weather patterns that will affect harvest cannot be ignored. In this way, full participation of growers, storage operators, shippers, and other industry personnel can ensure that fruit of appropriate quality are received in the marketplace.

Related Topics: HARVEST; PACKING; PHYSIOLOGICAL DISORDERS; POSTHARVEST FRUIT PHYSIOLOGY; PROCESSING; STORING AND HANDLING FRUIT

SELECTED BIBLIOGRAPHY

Abdi, N., P. Holford, W. B. McGlasson, and Y. Mizrahi (1997). Ripening behavior and responses to propylene in four cultivars of Japanese type plums. Postharvest Biol. Technol. 12:21-34.

Beaudry, R., P. Schwallier, and M. Lennington (1993). Apple maturity prediction: An extension tool to aid fruit storage decisions. HortTechnol. 3:233-239.

Blanpied, G. D. andK. J. Silsby (1992). Predicting harvest date windows for apple, Info. bull. 221. Ithaca, NY: Cornell Coop. Ext. Serv.

Crisosto, C. H. (1994). Stone fruit maturity: A descriptive review. Postharvest News Info. 5:65N-68N.

Hansen, E. and W. M. Mellenthin (1979). Commercial handling and storage practices for winter pears, Agric. exper. sta. special report 550. Corvallis, Oregon: Oregon State Univ.

Looney, N. E., A. D. Webster, and E. M. Kupferman (1996). Harvesting and handling sweet cherries for the fresh market. In Webster, A. D. and N. E. Looney (eds.), Cherries: Crop physiology, production and uses (pp. 411-441). Oxon, UK: CAB International.

Reid, M. S. (1992). Maturation and maturity indices. In Kader, A. A. (ed.), Post-harvest technology of horticultural crops, Bull. 3311 (pp. 21-30). Oakland, CA: Univ. of California.

Watada, A. E., R. C. Herner, A. A. Kader, R. J. Romani, and G. L. Staby (1984). Terminology for the description of developmental stages of horticultural crops. HortScience 19:20-21.

Watkins, C. B. (2002). Principles and practices of postharvest handling and stress. In Ferree, D. C. and I. J. Warrington (eds.), Apples: Crop physiology, production and uses. Oxon, UK: CAB International. In press.

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