Avocados have had the most sustained moment in the spotlight of any food except maybe bacon. And it's no wonder. Not only are they incredibly delicious (like bacon), they're also powerhouses of nutrition (not like bacon!), plus they're key for making guacamole. Some of us have no trouble polishing off an entire avocado in one sitting. But for those of us who eat half at a time, how best to keep the other half from turning brown before our next avocado toast or salad can be worrisome. I put six popular methods to a 24-hour fridge test to find the best method for how to keep avocado fresh and green.
Method #1: Top with plastic wrap
Ideally, plastic wrap should create an airtight seal, thus preventing the avocado from oxidizing. I first wrapped it tightly with plastic, then pressed the pit back into place to create a better seal all around.
The verdict: There were some air pockets creating some pretty significant browning.
RELATED: How to keep guacamole green
Method #2: Rub with lemon juice and top with plastic wrap
Ascorbic acid (aka vitamin C) combats the enzyme (polyphenol oxidase) responsible for avocados from turning brown. It works pretty well for guacamole, so by extension, it should do the same on avocados. I rubbed the surface well with lemon juice and wrapped it in plastic.
The verdict: The avocado was only slightly less brown than plastic wrap, but the acid in the juice broke down the avocado a bit and the surface was a little mushy.
Method #3: Brush with olive oil and top with plastic wrap
Like lemon juice, olive oil contains acids — linoleic, palmitic, and oleic to name just 3 — so maybe it would combat oxidation. I brushed the surface all over with olive oil and wrapped it in plastic.
The verdict: It was significantly browner than the previous methods and had an oily, slick, and slightly mushy texture.
Method #4: Dunk in water and top with plastic wrap
A thin layer of water is hands down, the best way to keep guacamole green, so it made sense that it would be as effective on avocados. I submerged an avocado in a bowl of cold water and covered it with plastic.
The verdict: Not so brown, but the avocado was water-logged and the texture was unpleasantly mushy.
Method #5: Use a gadget
I tested out the Savel by Dreamfarm, a flexible food saver that covers cut food to keep it fresh.
The verdict: ADORABLE! But not perfectly suited to avocados. There was some browning. It's much better suited to acidic fruits or vegetables like lemons, or tomatoes.
Method #6: Place in a plastic container with a cut onion
Sulfur dioxide is a compound used to preserve fruits. Think dried apricots. The unsulfured ones are dark brown and pretty unappealing looking. Those treated with sulfur dioxide are bright orange. Sulfur is a component in onions, so it stood to reason it might work similarly. I put a halved onion with the avocado in an airtight container overnight.
The verdict: By far, the best of all methods, the avocado was nearly as green as when it was cut. Now, bring on the guacamole!