Recommendations for Maintaining Postharvest Quality
Maturity & Quality
In most of the cultivars growing in California, harvest date is determined by skin color changes that are described for each cultivar. A color chip guide has been designed to determine maturity for each cultivar.
Measurement of fruit firmness is recommended for cultivars where skin ground color is masked by full red or dark color development before maturation.
Maturity & Quality Photos
Temperature & Controlled Atmosphere
-1.0 to 0°C (30.5-32°F)
90-95% R.H; an air velocity of approximately 50 CFM is suggested.
To calculate heat production multiply ml CO2/kg·hr by 440 to get BTU/ton/day or by 122 to get kcal/metric ton/day.
Rates of Ethylene
*The lower end of this range is for mature but unripe fruit; higher values are for ripe fruit.
Most of the plums harvested at the California Well-Mature stage (higher than US-Mature) will ripen properly without exogenous ethylene application. Ethylene application to fruit harvested at the US-Mature maturity will only ripen the fruit more uniformly without speeding up the rate of ripening. However, for the slow ripening plum cultivars, expgenours application of ethylene (100 ppm for 1-3 days at 20°C/68°F) is needed for even ripening. These cultivars are Angeleno, Black Beaut, Casselman, Late Santa Rosa, Kelsey, Nubiana, Queen Ann, Red Rosa, and Roysum.
The major benefits of CA during storage/shipment are retention of fruit firmness and ground color. Decay incidence has not been reduced by CA of 1-2% O2 + 3-5% CO2. CA conditions of 6% O2 + 17% CO2 are suggested for reduction of internal breakdown during shipment, but its effectiveness depends on cultivar, preharvest factors, market life and shipping time.
Market life varies among cultivars and it is strongly practices on affected by temperature management. Maximum market life is obtained when fruit are stored at approximately 0°C (32°F). Maximum market life varies from 1-8 weeks. Because internal breakdown is the main limitation to market life, minimum postharvest life occurs when fruit is stored at 5°C (41°F).
Temperature & Controlled Atmosphere Photos
Physiological and Physical Disorders
[For more information, see our publications “Fruit Ripening & Ethylene Management”, and “Peaches, Plums, and Nectarines-Growing and Handling for Fresh Market”, available for purchase using our Order Form.]
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How to Cite
Author(s) names. Initial publication or update date (located at the top). Title. Link to the specific Produce Fact Sheet webpage (Accessed date)
Example: Cantwell, M. and T. Suslow. 2002. Lettuce, Crisphead: Recommendations for Maintaining Postharvest Quality.