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Avocados are a notoriously tricky fruit to store. If you buy the fruits when they are already ripe, you'll need to use them immediately or they may rot in a day or two. However, if you buy them before they are ripe, you may not remember to check them for ripeness and then find that they've ripened and rotted before you've had a chance to use them. Fortunately, there are ways to both hasten the fruit's ripeness and to delay it.

When's the Best Time to Eat an Avocado?

It can be tough to tell when an avocado is ripe because it goes from hard to too soft very quickly. A good rule of thumb is to look at the skin. If it's very bright green and firm to the touch chances are it's not ripe yet. However, if the skin is a blackish color, and pressing lightly on the outside leaves a deep indentation, the fruit is too ripe.

A ripe avocado should have a near-black skin and be slightly firm but also slightly pliable, like the area on your hand just below where your thumb connects to your palm. Another way to check the ripeness of an avocado is to pull off the tiny remainder of the stem that sits at the very top. If the color you see beneath the stem is a soft, bright green, the fruit is ready to eat. If it's brown, it's either overripe or not ripe yet.

How to Stop Avocados From Ripening

While it can be difficult to tell exactly how ripe an avocado is, it's easier to keep an avocado from ripening than it is to make a ripe avocado stay ripe instead of going bad. When you buy avocado from the store, and you can tell that it hasn't ripened yet, you do have an option: Putting the avocado in the refrigerator will likely delay its ripening for about two to three days.

Once you've left it in the refrigerator for that long, take it out and give it about a day to get perfectly ripe. You can check on it periodically by testing its firmness and looking at the skin under the stem. But don't miss that window, because once an avocado is ripened, there is no going back.

If an avocado is already ripe, putting it in the fridge won't help you much. You'll be basically abandoning a ripe avocado to slowly over-ripen. It's best to employ the refrigerator as a ripener-slowing device only for fruit that hasn't reached its peak ripeness yet.

How to Ripen an Avocado

If, on the other hand, you are in the opposite position and need to hasten the ripening of an avocado, there are things you can do. Placing an unripe avocado in a paper bag, along with an apple or a banana will help to ripen the fruit more quickly.

Storing a Cut Avocado

Storing a cut avocado can present a lot of difficulties. While you can stop avocados from ripening, consult an avocado ripening chart, and even hurry along an avocado's ripening, these are all things that you do with avocados that haven't been cut. A cut avocado is much more difficult to store.

Once the avocado is cut, the air exposes the flesh to oxidation. This is why avocados turn brown. However, spritzing the surface of the avocado with lemon juice and placing it in an airtight container in the refrigerator can help to delay the oxidation process. Store the lemon-bathed avocado in your refrigerator, protected in plastic wrap and an airtight container, and it will last for about a day.