Updated: May 24, 2020
It can be tricky to choose produce at the store or farmers' market if you don't know how to pick ripe fruits and veggies. I bought a pineapple recently and waited and waited for it to ripen on my counter. Then I learned that pineapples don't ripen after they're picked.
It's important to know which fruits and veggies will continue to ripen after harvest, and which ones will sit hard on the counter until they rot. Scroll down for a list.
Ethylene Gas Ripens Some Produce
The main factor that influences ripening after harvest is ethylene gas. Prime example: Bananas.
Bananas are known to ripen and brown once you bring them home. Ethylene is responsible for browning the bananas after they've been picked. In fact, if you put other fruits in a bag with a banana, the ethylene gas can ripen the other fruits as well.
Note: This will only work during a certain window of time with certain fruits and vegetables. If you put a young apple in a bag with a banana too early, the ethylene gas will have no affect on its ripening, or even prevent it from ripening altogether. The fruit has to be in the window of time close to its ripeness. (1)
But not all fruits will ripen with ethylene gas! Some fruits must ripen on the vine, tree, or bush and picked at the precise right time in order to provide the most flavor, color, and nutrients that we love. The fruit isn't stubborn, but just isn't affected by the ethylene hormone.
Which fruits ripen after being picked?
Here's a quick list of fruits that will ripen on your counter after being picked:
Which fruits don't ripen after being picked?
These fruits will not ripen after being picked so should be carefully chosen at the store or market before you bring them home:
How to Choose the Best Fruits & Vegetables
If you're choosing a fruit or vegetable that won't ripen after being picked, how do you know if it's ripe? There are some tricks to know how to choose the best, perfectly ripe fruit or vegetable.
Avocados will continue to ripen after they're picked. But if you've ever bought one, you know it can be difficult to judge how long it will take to ripen... or if it's already past its expiration. When choosing avocados at the store, the stem stump should still be attached. The skin can be brown or green. When you squeeze the avocado, it should still be firm with some give, but not so soft that it feels mushy. Once you get it home, if the stump loosens enough to easily come off and the fruit is soft, the avocado is ready to eat.
Crispy carrots are ideal. If the carrots still have the tops on, it's important to remove them before refrigerating the carrots because the tops extract nutrients from the flesh.
The size of a garlic bulb dictates its pungency. The bigger it is, the milder the flavor. Avoid garlic bulbs that have signs of rot such as brown circles or areas that look eaten away.
Heavy, firm, but springy are the qualities of a ripe grapefruit. If it has a soft spot at the stem, the fruit should not be eaten. Did you know that grapefruit are juicier when warm? They can be stored on the counter for a week.
Firm tomatoes without cuts and bruises are the safest. Due to their high moisture level, tomatoes are very susceptible to bacteria that can cause foodborne illness. Avoiding cuts and bruises is less a matter of cosmetics than it is of safety.
The surface of a watermelon should be dull (not shiny). Look for a yellow bottom instead of white or green.
Pineapples don't ripen after
harvest. If a leaf comes out easily at the store, it's ready to eat. If not, don't buy it. Also, choose large, firm, yellow, and fragrant fruit. Avoid those with bruises, soft spots, or discolored areas.
Look for firm, glossy, bright red berries with green stems. Avoid strawberries with white tips because they were picked before ripening all the way. Strawberries will not continue to ripen after being picked. Although they continue to darken in color, they will not taste any sweeter. Keep strawberries refrigerated. Only wash strawberries right before eating to prevent mold growth. You can let them sit at room temperature for up to 30 minutes to intensify the flavor.
Look for firm, not rotted potatoes; sprouts are ok. However, if you find a potato with green on its skin DO NOT EAT IT. The green is chlorophyll and a sign of a toxin called solanine, a natural defense mechanism potatoes use to ward off pests. There are cases of illness from eating green potatoes as severe as paralysis and death. (2)
Ehrenberg, R. (2018). Science reveals how fruit keeps a lid on ripening until the time is right. National Public Radio. https://www.npr.org/sections/thesalt/2018/09/24/650585212/science-reveals-how-fruit-keeps-a-lid-on-ripening-until-the-time-is-right
North Dakota State University. (Aug. 2015). From garden to table: My potatoes turned green. Now what? https://www.ag.ndsu.edu/publications/lawns-gardens-trees/from-garden-to-table-my-potatoes-turned-green-now-what#section-1
To learn more nutrition tips or to make a virtual nutrition appointment with a registered dietitian, visit ZEST Nutrition.