Avocados begin to turn brown when the fruit is exposed to oxygen. Image: Flickr

The best ways to prevent your cut avocado from turning brown

Avocados’ tendency to brown quickly can be frustrating, but some of the tricks to keep them green are risky.


Avocados begin to turn brown when the fruit is exposed to oxygen. Image: Flickr

Are you planning to eat half the Avo now and the other half tomorrow? While there are numerous hacks to keep cut avocados fresh, some of these tips and tricks can make you seriously ill.

Avocados are packed with fibre and potassium and are a plant-based source of healthy fats. They’re a wildly popular South African fruit, but they can also turn on you if you don’t store them properly.

Here’s how to keep your avocados from turning brown (without compromising your health.)

Understanding the browning process

Avocados start to brown due to a process called oxidation, which occurs when the fruit is exposed to oxygen. This reaction isn’t harmful, but it can make the avocado look less appealing and cause the flesh to form a hard outer layer.

To maintain that vibrant green colour, you need to slow down the oxidation process.

Safe and effective methods to prevent browning

Use Citrus Juice

Squeeze lemon or lime juice onto the exposed surface of the cut avocado. The citric acid in these fruits slows down oxidation. Next, wrap the avocado tightly in plastic wrap to minimise air exposure and refrigerate.

The Onion Method

Onions contain sulfur, which can prevent the enzymes in avocados from interacting with the air.

To take advantage of this trick, cut up some onion, line the bottom of an air-tight container, and place the avocado on top of the onion slices with the cut-side up. Then cover and store in the fridge.

Brushing with Olive Oil

Some suggest that brushing the cut avocado with a thin layer of olive oil can save it from turning brown, at least for a day or two. The idea is that the oil creates a barrier, reducing oxygen exposure.

Once you’ve done this, wrap the avocado in clingwrap and store it in the fridge.

What about submerging avos in water?

As popularised by various social media trends, some have suggested that storing whole or cut avocados in water keeps them fresher for longer.

This may prevent oxidation in the short term, but it is not advisable for longer storage as prolonged submersion comes with health risks.

According to the FDA, the practice can promote the growth of harmful bacteria such as Listeria monocytogenes and salmonella.

These bacteria can cause severe illnesses, including fever, diarrhoea, and abdominal cramps, especially in individuals with weakened immune systems.

“The main concern is the possibility that any residual human pathogens that may be residing on the avocado’s surface may multiply during the storage when submerged in water,” notes Janell Goodwin from the FDA.

Freezing avocados

Refrigeration can extend the life of a ripe avo for a day or two. For longer storage, freezing is a safe and effective practice and can be done in various ways.

With this method, cut the avocado into quarters, remove the skin, and place the pieces in a resealable plastic bag. Add a little lemon or lime juice and store the bag flat in the freezer.

It’s important to note that freezing may slightly alter the texture, so this method is best for avocados you plan to use in smoothies or blended recipes.