The plantain is a Latin American fruit related to the banana. Their textures and flavors vary, though. Plantains have thick skin, which is harder to peel than a banana's skin, and their flavor is starchy rather than sweet. Most consumers use them like vegetables and cook them, since the firm texture and starchy taste make them difficult to eat raw, unless they ripen long enough to become black and sweet. The fruit takes days to ripen and does not spoil quickly. You can ensure or prolong a plantain's shelf life by following certain guidelines.
A plantain's color is the first indicator of the fruit's remaining shelf life. They progress from green to yellow to black. It is safe to eat plantains in any color stage as long as they remain firm and show no visible signs of damage. The longer you need the plantains to last, the earlier in the color development process they should be when you acquire them. Yellow plantains may have some dark spots. The darker the plantain is, the sweeter it is. A yellow plantain with no spots would not taste as sweet as a yellow plantain with several dark spots.
Plantains ripen slowly over the course of days. The length of the ripening process depends on two qualities: the color of the plantains when you purchase them and the color you want them to become. For example, if you need black plantains for a baking recipe and you purchase green plantains, you could buy the fruit up to two weeks in advance of using them. Place plantains on your kitchen counter when you bring them home from the market. Leave them out to ripen at room temperature. The plantains should reach your desired color within one or two weeks. Transfer the plantains to a refrigerator to halt the ripening process.
Plantains, like bananas, freeze well. The University of Kentucky Department of Agriculture states that plantains last eight to 12 months if you prepare them properly. (See Ref 1) The most effective way to prepare them for freezing is to mash them. Slice the top and bottom ends off the fruit. Score a line down the thick peel with a knife. Remove the peel, and place the fruit in a bowl. Add 1 teaspoon of lemon juice for every plantain you place in the bowl. The acid in lemon juice prevents the exposed plantain flesh from browning. Mash the plantain with a fork or potato masher until the consistency is even. Store mashed plantains in an airtight container.
Time your plantain purchase appropriately to ensure you get maximum use out of it. Plan and schedule the recipe for which you need the plantains in advance of buying the fruit. Consider the amount of time you need to ripen the fruit. For example, if you want to eat raw plantains at a picnic, buy the fruit two weeks ahead of the picnic so that they have adequate time to become black. If you want plantains for a Latin American, spicy fritter recipe, you need firm, green plantains. Therefore, you should purchase the fruit one or two days ahead of preparing the dish.