This Is How to Keep Guacamole from Turning Brown

Updated: Jan. 23, 2024

Make party-ready guacamole days in advance—or keep leftovers fresh for later. Here's how to keep guacamole from turning brown.

If you want to make guacamole in advance but don’t want it to look like a science experiment once it hits the buffet table, I can relate. Unfortunately, when exposed to air for too long, polyphenol oxidase (read: the stuff found in an avocado’s chemical makeup) causes guacamole to become mushy and brown. No thanks!

There’s always the option to pick up one of our Test Kitchen’s picks of best guacamole brands at the store, but if your heart’s set on homemade guacamole, then grab a couple ripe avocados and read on.

Bonus: If you’re interested in knowing how to keep your guacamole looking and tasting fresh for up to a week, we’ve got the perfect kitchen gadget for you—the Guac Lock.

How to Keep Guacamole from Turning Brown

person adding water to the top of a container of guacamoleTMB Studio

What’s the secret? Cover the guacamole with 1/2-inch of water. It might sound strange, but the extra layer shields the dip from oxygen and thwarts browning. For best results, follow these steps:

1. Place guacamole in a sealed container

It’s critical that the guacamole be stored in an airtight container—like these glass storage containers—rather than, say, a bowl covered with foil. Using an airtight container keeps the amount of oxygen coming into contact with the guacamole to a minimum. It also locks out moisture and humidity, which maintains food’s freshness.

2. Use a spoon to smooth out surface

With a metal spoon, flatten the surface, taking care to remove all air pockets. If you haven’t already caught on, air is an avocado’s enemy. By reducing the chances of the guacamole coming into contact with air, you reduce the chances of discoloration.

3. Pour water over the guacamole

Fill a measuring cup with water that’s cool or room temperature. Gently pour about a half inch of liquid over the top of the dip. Make sure water covers the surface completely—all the way to the container’s edge.

Editor’s Tip: You may have heard a squirt of lemon or lime juice also keeps guacamole from browning. It’s true—as long as you cover the entire surface of the dip with citrus juice.

4. Store guacamole in fridge

Refrigerate the container of guacamole, covered tightly, for up to two days.

To serve, carefully pour off the water and stir the guacamole. Now it’s time to pull out the best tortilla chips and get dippin’!

FAQs About Storing Guacamole

Why does guacamole turn brown?

Guacamole in a blue bowl with a few tortilla chips surrounding on a marble surfaceTMB STUDIO

The enzyme polyphenol oxidase reacts with oxygen and discolors the avocado. It’s the same chemical process that causes other produce like potatoes or apples to turn brown. Since oxidation turns avocados brown it also impacts a bowl of guacamole.

Is it OK to eat guacamole when it turns brown?

Yes. It’s safe to eat! Well, it’s safe as long as the guac has been stored in the fridge for not longer than two or three days. It may not look as appetizing as a fresh bowl of guac but like a brown avocado, brown guacamole can be safely eaten.