From the UC Davis Post-Harvest Technology Center
The flavor of fruits and vegetables is influenced by maturity and quality at harvest and by how they are stored afterwards. To maintain the freshness and flavor of the produce you buy at the market or grow in your garden, it is important to know how to store it at home.
Many fruits and vegetables should be stored only at room temperature because refrigerator temperatures (usually 38° to 42°F) damage them or prevent them from ripening to good flavor and texture. For example, when stored in the refrigerator, bananas develop black skin and do not gain good sweetness, and sweet potatoes take on off-flavors and a hard core when cooked after being refrigerated. Watermelons lose their flavor and deep red color if they are stored for longer than 3 days in the refrigerator. Pink tomatoes ripen to a better taste and red color if they are left at room temperature. In the refrigerator, they do not turn red, and even red tomatoes kept in the refrigerator lose their flavor.
Other produce can be ripened on the counter and then stored in the refrigerator. A few fruits and fruit-type vegetables gain sugar or soften when stored at room temperature. For example, Bartlett pears turn yellow and become softer and sweeter on the counter. After they have ripened they can be stored for 1 to 3 days in the refrigerator without losing taste.
The counter storage area should be away from direct sunlight to prevent produce from becoming too warm. Fruits and vegetables that can be stored at room temperature for a few days without shriveling do not lose moisture rapidly. Even so, moisture loss can be reduced by placing produce in a vented plastic bowl or a perforated plastic bag. Do not place produce in sealed plastic bags on the counter because this slows ripening and may increase off-odors and decay due to accumulation of carbon dioxide and depletion of oxygen inside the sealed bag.
Ripening in a bowl or paper bag can be enhanced by placing one ripe apple with every 5 to 7 pieces of fruit to be ripened. Apples produce ethylene that speeds ripening. (Fuji and Granny Smith apples do not produce much ethylene and do not enhance ripening.)
Refrigerated fruits and vegetables should be kept in perforated plastic bags in the produce drawers of the refrigerator. You can either purchase perforated plastic bags or make small holes with a sharp object in unperforated plastic bags (about 20 holes per medium-size bag). Separate fruits from vegetables (use one drawer for each group) to minimize the detrimental effects of ethylene (produced by the fruits) on the vegetables. Use all refrigerated fruits and vegetables within a few days since longer storage results in loss of freshness and flavor.