As many guacamole aficionados and millennials know, the avocado is a fickle sort of fruit. When creamy, green, and lusciously smooth, it’s the go-to topping for bread, eggs, sushi, and salads. But in the blink of an eye, and when least expected, its vibrant green flesh can darken, taking on a mushy texture and emitting a rancid smell.

Fortunately, with the right knowledge and tips, you’ll be able to have ripe avocados all the time. Whether you’re hoping to buy a ready-to-go avocado, ripen the fruit at home, or eat half now and save the rest for lunch tomorrow, here are essential things to know about this creamy fruit.

What is an avocado?

Native to Central America, the avocado was first domesticated around 5,000 years ago by Mesoamericans. Today its most popular variety is the Hass, which was first grown nearly a century ago by Rudolph Hass in La Habra Heights, California. Botanically speaking, the avocado is a single-seed berry containing little or no sugar and starch. But it has lots of oil, 15% in fact. Now, with over 500 varieties, from the popular Hass to the hardy, pear-shaped Fuerte and Zutano, this fleshy fruit has become a favorite in many recipes and kitchens.

Buy an avocado at a grocery store and chances are it’s a Hass. Farmers across growing regions in California, Mexico, and Indonesia alike prefer the Hass because it can withstand longer shipping times. In the US this variety alone accounts for around 95% of the avocado crop. Outside the country, Mexico remains the largest exporter of avocados year-round, especially in the prolific avocado state of Michoacán.

Like many fruits out there, avocados are climacteric, which means they ripen after they’ve been picked. Once plucked off the tree, the avocado begins releasing ethylene, a natural gas that contributes to its ripening. It’s then stored in cool temperatures away from other ethylene-emitting produce such as apples, bananas, and peaches. Once the fruit is moved to room temperature, they will begin ripening at a normal rate.

How to tell if an avocado is ripe

Given a mountainous pile of avocados, how do you pick one that’s unequivocally creamy and green? The answer really depends on whether you want to eat it immediately or save it for later in the week. To choose the ripest avocado at the supermarket, rely on your sense of touch. Lightly grasp the avocado in your hand without denting the skin with your fingers. If it’s hard, it’s unripe. But if it’s soft and yields gently to pressure, it’s ripe and ready for consumption.

You can also try fiddling with the avocado stem. If the small part of the stem comes off when gently tapped, the avocado has already begun ripening and may be past its ripe stage when you take it home. Try to avoid avocados with any sort of space between the skin and fruit. “If it's got any kind of gap between the skin and the flesh, don't buy that avocado,” says Lara Ferroni, author of An Avocado a Day: More than 70 Recipes for Enjoying Nature's Most Delicious Superfood.

Color plays a surprisingly small role in indicating avocado ripeness, according to Miguel Gonzalez, a New York City avocado supplier known as Davocadoguy. Depending on the season, he says, a black avocado could be rock hard while a green avocado could be overripe. Because other non-Hass avocados can differ in color and texture, never solely rely on the outer appearance when selecting this fruit.

Where you buy your avocados matters too. Grocery stores tend to store all their produce at similar temperatures, which may actually damage the temperature-sensitive avocado. And a soft avocado can bruise easily if stored or handled incorrectly, especially if shoppers are pressing too hard on its skin. On the other hand, specialized suppliers and farms that sell direct may have better storage options. For instance, Gonzalez keeps his avocados in multiple temperature-controlled rooms, sections them off by harvest date, and arranges them neatly in boxes to protect their flesh.

How to achieve perfect ripeness at home

Most people are familiar with the paper bag method: Stick an avocado in a paper bag with an ethylene-emitting banana or apple, which will expedite its ripening process. But this handy trick can backfire, especially if you’re trying to preserve your avocados for longer periods of time.

Gonzalez approaches the paper bag method warily and comments that it might be “the worst thing you can do.” As a supplier to high-end restaurants like Casa Enrique and Daniel in New York, Gonzalez understands the value of a peak avocado. Since the bag acts as an insulator, allowing the avocados to release and store gases in a tiny space, the avocado will ultimately ripen faster but potentially overshoot its peak ripeness. He views this technique as a double-edged sword—a quick and dirty solution if you’re in a pinch—and ultimately recommends ripening avocado in a cool place not prone to temperature fluctuations.

But perhaps you’ve used the paper bag method and find yourself with a set of ripe avocados on hand. You could eat them all in one sitting, or you could stick them in the fridge and extend their shelf life for a few more days. Just make sure that your avocados are ripe before relying on the fridge. Sticking an avocado in the fridge too early can actually prevent its ripening. According to Harold McGee in On Food and Cooking, a chilly fridge can damage the cellular machinery of these warm-climate fruits and they will sadly never ripen.

If you find yourself cooking with avocados throughout the week, Megan Warren of Shanley Farms in California recommends buying a bag of avocados and storing them in several places. She’ll put some on the counter, some in a paper bag, and tuck away the rest in the refrigerator after they ripen. This way it ensures she’ll always have an avocado within reach.

Freezing avocados can also help prolong their shelf life. You can place ripe avocados with either the skin on or off in the freezer and defrost them whenever you’re craving some. Unfortunately, freezer avocados have a slightly mushier texture than fresh ones and work best in baked goods and blended foods such as smoothies rather than avocado toast.

How to store a cut avocado

Now let’s say you’ve opened an avocado but stopped short of finishing the whole thing. You could add a few drops of oil and lay it face down on an oiled plate in the fridge, but this may fail if any part of the fruit is exposed to oxygen. Some internet sources have recommended submerging the avocados, skin down, in water. But this hack comes with its own risks, including the presence of avocado-skin-borne pathogens such as salmonella or listeria monocytogenes that may lurk in the water.

Instead, here are a few safer strategies to extend the life of your avocado. To prevent oxidation (a.k.a. browning) on an avocado surface, splash some lemon or lime juice (or a sprinkle of citric acid) over the fruit and wrap it tightly in plastic or a designated avocado hugger before placing it in the fridge. The citric acid also comes in handy to preserve a bowl of freshly made guacamole so you can munch on it after Sunday night game day.

How to salvage a bad avocado

Sometimes an unripe or overripe avocado may land on your doorstep. As long as they aren’t rancid-smelling or deeply brown and black inside, you can manipulate an underripe or overripe avocado to fit your culinary needs.

Given a bag of unripe avocados, Warren recommends using slightly firmer avocados for ceviche. “It's perfect in ceviche because you have to slice them up really small and you want that chunky situation.” Ferroni, who has explored hundreds of ways to use avocados, adds that a firm avocado works well for skewers, especially when placed for two to three minutes on a hot charcoal grill. (But fair warning: Since avocados are a high-fat fruit, prolonged contact with fire will cause the avocado flesh to develop a bitter and astringent taste.) Unripe avocados can also be used for fries, Gonzalez adds, which can be coated in panko or breadcrumbs and fried or baked for a crunchy, creamy bite.

While you may be tempted to toss overripe avocados, the world of baking and smoothies beckons you to give the fruit another life. Avocados make the perfect fat substitute for melted butter or oil (1:1 ratio), so you can chuck an overripe avocado into a cake or brownie recipe. Or freeze the avocados to whip up a thick smoothie—or tangy avocado margarita—in a pinch.

Originally Appeared on Epicurious

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