Which vegetables shouldn't be stored in the refrigerator? Which ones are best left out?

Why it's better not to put them in the refrigerator

The low temperatures of the refrigerator—from 2°C to 8/10°C—generally allow foods to retain their original characteristics longer and be brought to the table safely, as the cold slows the proliferation of bacteria. In certain cases, however, they can contribute to accelerate the deterioration process, particularly because the refrigerator is a closed and humid environment, conducive to mold growth. Onions and garlic soften and tend to mold due to humidity, while tomatoes and cut squash rapidly lose moisture, texture, and flavor.

Potatoes undergo a chemical change that alters their texture and flavor, and potentially even their healthiness. The cold turns starches into sugars, resulting in a higher risk of producing acrylamide during cooking, a substance harmful to health. Furthermore, potatoes, garlic, and onions may sprout. Avocado should only be refrigerated when ripe (which isn't always easy to verify) or when it goes from unripe to rotten. Basil leaves, meanwhile, suffer chilling injury, causing them to blacken and rot quickly, destroying the essential oils that give them their characteristic aroma.

How to store them correctly

Vegetables that don't adapt well to the humidity and cold of the refrigerator should be stored elsewhere: they are different vegetables, each with its own specific needs. For some, a dark pantry is the ideal place; others can be stored in a basket or on a plate on the table or kitchen cabinet, all of which are kept at room temperature. Let's look at them in detail.

1. Onions

The first rule of onions is to find a dark place. These vegetables naturally grow underground, and to best preserve them, it's helpful to recreate similar conditions as much as possible. The pantry is the place to go: these bulbs require a dark environment that's also dry and ventilated, ensuring adequate ventilation. You can also opt for a cellar, placing them in perforated cardboard or a wooden or plastic crate if you've stocked up, as long as the space doesn't get too cold and humid.

2. Garlic

The same precautions you took for onions apply to optimally store garlic in the pantry or cellar, preferably hanging it to allow air to circulate and prevent mold. Despite the potentially unpleasant odor, avoid storing whole heads in an airtight container or plastic bag.

3. Potatoes

Potatoes are vegetables that can last for months at room temperature, but even when left out of the refrigerator, they often shrivel, turn green, and sprout. The main causes are usually keeping them exposed to light or in a stagnant pantry, which builds up humidity. Potatoes prefer dark, airy, and dry places, ideally stored in a paper bag that protects them from the sun's rays while still allowing them to breathe.

4. Tomatoes

Tomatoes are climacteric fruits, and depending on when you buy them, you should encourage their natural ripening. They're best on the sideboard, on a plate, or in a basket where they can continue to breathe: avoid direct light and heat, which risk altering their consistency and flavor. If you want them to ripen faster while still unripe, store them in a paper bag with ripe bananas, which also produce the hormone ethylene after harvest. The only exception to this rule is if the kitchen is excessively hot, such as in the summer or with the radiators turned up to full blast in the winter.

5. Pumpkin

The size of pumpkins makes the refrigerator a no-no for practical reasons: it would take up too much space. Fortunately, they're a hardy vegetable that will last for many months if stored in a cool, dry, and well-ventilated place, away from heat and direct light. A cellar or closet is usually the best choice. Make sure there's not too much humidity, as this could lead to rotting, and check that the peel is intact and undamaged, otherwise the shelf life will be drastically shortened.

6. Avocado

Storing avocados depends primarily on their ripeness. If they're not yet ready to eat, room temperature is the perfect ally: they ripen slowly when placed on a plate or basket like tomatoes, while they ripen faster in a paper bag next to bananas or apples, thanks to the action of ethylene. The refrigerator comes in handy when the avocado is ready to eat, but you can't do it right away and want to extend its shelf life for 2-3 days at most.

7. Basil

We conclude with the bunch of basil: to maintain the bright green and enveloping scent of this aromatic herb, the best way is to treat it like a bouquet of flowers, using a vase or glass of water and immersing the end of the stem of the plant. Change the water daily and keep away from direct light and heat sources.

When to store them in the refrigerator

The best practices described above apply to whole, intact vegetables, with the peel or surface layers acting as a barrier to external agents, protecting the most delicate part, the pulp. For this very reason, once cut, most vegetables should be refrigerated, otherwise they are susceptible to oxidation and rapid deterioration. While airtight containers were once a major enemy, they are now one of the best options, for example for tomatoes, squash, and avocados: the latter quickly turns brown, and it's recommended to sprinkle them with a few drops of lemon juice to slow the discoloration. Sliced ​​or diced potatoes can be stored in the refrigerator in a bowl of cold water acidulated with a little vinegar or lemon juice (avoiding salt, which would extract the liquid through osmosis).

Peeled garlic and onion must be well-sealed or they will release their characteristic pungent aromas. For the former, use glass containers (plastic ones could absorb odors), while the latter can be wrapped in plastic wrap. Wash and dry the basil leaves thoroughly, then place them in a container covered with slightly damp paper towels to prevent them from drying out. A final tip: don't leave chopped or chopped vegetables in the refrigerator for more than 48 hours or you risk wasting them. A whole peeled garlic clove can last up to a week.