I sometimes don't need a whole avocado, especially when I'm making food for just me, so I'm often left with a spare avocado half. As we all know, the cut surface of an avocado quickly turns brown and slimy, making it hard to store it in the refrigerator for very long. Read on for my best tip ever for keeping a cut avocado green, fresh and tasty! (And no, it does not involve the pit!)
Why do avocados turn brown when cut open? The Omega-3 fatty acids found in avocados are sensitive to light, air and heat and easily oxidize when exposed to them, causing them to brown and break down. This is why an avocado is often green underneath the pit but brown on the exposed surfaces surrounding it - the surface underneath the pit is protected from light and air. So it's not about the pit itself, only the way the pit acts as a barrier.
The Usual Solution: So the best thing to do is to limit the exposure of the cut surface to air, light, and heat. Many people simply press a piece of plastic wrap over the cut surface and stick it in the refrigerator. I've tried this and I've found it lacking. First, I don't like plastic wrap and second, it seldom creates a tight enough seal to keep the air out.
Another solution is to squirt it with lemon or lime juice but I've found that over time this just makes for a slimy avocado. Ugh.
My Solution: Place the avocado in a clean cottage cheese or similarly sized opaque container with a piece of cut up onion. Cover with lid and refrigerate. I've had a cut avocado stay fresh for several days this way. I don't know why this is, but I suspect that it has to do with the sulfuric acids that the onion releases. This is the same sulfur that makes you cry when you chop onions, but it is also used as a preservative. The onion smell/taste doesn't seem to transfer to the avocado, as far as I can tell. But I'm not overly sensitive to onions, so you may want to check this out first if you are.
The Guacamole Solution: Pressing plastic wrap over the guacamole to seal out the air and placing it in the refrigerator works really well. But if you want to avoid using plastic wrap, I've found that scattering some of the chopped onion called for in the recipe over the top of the guacamole, then wrapping the bowl in foil, or covering it with a plate, works really well. Just stir in the onion and serve!
Related: Recipe: Avocado Hollandaise
(Image: Craig Stephens)
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Comments (46)
This is amazing, I can't wait to try it. I LOVE avocado but often avoid buying it because I waste so much of what I can't eat fast enough. Thanks!
Wow, thanks so much for this! I'm always frustrated when my avocado turns brown!
I can't wait to try this! I thought I'd tried everything. I usually default to the lemon/lime juice method. I try to just make an effort to finish the avocado by the next day to minimize the damage. But this is exciting!
Who could have guessed... I often throw away pieces of avocado because of the way they look after a day in the fridge, so I'll definitely try this!
I will try this! I love guacamole, but my husband hates it, so I end up eating it myself and it always goes brown around the edges, no matter how I try to seal it.
if you spread a very thin layer of olive oil on the surface of the avocado and then wrap it in plastic wrap (or place it on a reusable piece of oilcloth, like an Abeego wrap) it will create more of a seal than the wrap alone. I have had avocados stay fresh this way for days, and the oil does not degrade the flesh the way that acids do.
Brilliant, thanks!
Storing it in a ziploc bag works just fine for me. I don't have to worry about cutting plastic wrap or adding flavors to the avocado.
Also, when I do leave it out sitting on the counter or when I'm stick in the fridge for a couple of hours before consuming again, I usually just slice off the ugly part. No major product loses here!
typos*
when I stick it in the fridge
Sorry about all these typos these morning. My brain is working in two languages simultaneously today.
OK, I just had to leave for a minute to do this. I used 1/4 of an avocado yesterday and always have some onion in the fridge. Done! If this works, it will be one of the best tips ever! (Not that I don't believe you, you know...)
I frequently use anywhere from 1/4 to 1/2 of an avocado at a time and what I always do is the following: if I'm only using a quarter, I essentially sandwich the avocado back together, with the pit still inside and wrap it in plastic wrap; if I'm using 1/2 of it, I leave the pit inside the remaining half and cover it withe plastic wrap. I refrigerate in both instances. I've never had a problem with discoloration.
When I use half of an avocado, I put a thin layer of olive oil on a small plate and place the cut side down in the oil. it creates an airtight seal and stays fresh for days.
The other day, I used half an avocado. I covered the remaining half in plastic wrap and put the wrapped piece into a ziploc resealable dish. It was just fine the next day. I hate the taste & smell of raw onions, so I'm very hesitant to try that, even if it does work. The olive oil trick that many of you are suggesting sounds better, though.
I just brush lemon juice over the exposed part and store wrapped, or in a container if the piece if large enough.
I never tried this method! I'm definitely going to try this. Thank you!
That's a beautiful portrait of avocados - where did you find it?
Nice tip! Though, most of the time I just end up eating the other half with a spoon.
I made a pork stew the other day to last me the week but refrained from getting an avocado to accompany it because I didn't want to waste half of the fruit. That will never happen again!
www.lickmyspoon.com
An ever better trick: put the avocado bag in a Ziploc vacuum sealer bag. Using the hand vacuum sealer pump takes out ALL the air! My avocados are seriously good SEVERAL days later. Genius.
My friend also keeps her cheeses in Ziploc vacuum bags and they last for months on end.
Hi Everyone: Thanks for all of your tips and tricks. Clearly this is an issue many of us want to solve!
HarkinB: The artist's name is Craig Stephens and his information can be found by clicking on his name at the bottom of the post where it says 'image.'
I never thought it was a big deal as the brown bit is such a tiny thin layer on top-- if it bothers you, you can scrape it off with a spoon with very little going to waste. if I'm mashing the avocado, I often don't bother and it doesn't affect the taste much, if at all (though this is only a day or so later).
As many stated above - air-tight or very little air will do the trick. Ziplock bags, small glass containers, etc.
I have an even easier way - to limit the amount of surface area that gets exposed to the air when you only need a small amount of avocado, just cut off the amount you need from the thin end of the avocado (where the stalk would be if it were still attached).
To preserve the rest, slather the remaining exposed part in olive oil and put in a ziplock bag and remove as much air as you can.
I can do this multiple times with the one avocado, keeping it lovely and fresh for many days.
if you leave the stone inside the "hole" after cutting the avocado it will stay fresh and greenish. the stone prevents the oxidation process.
Another vote for keeping the pit in place. Simpler solution.
I do something similar to Miss Neesh. I peel only the part I need from the thin end and store the rest in a zip lock bag in the fridge. The next day the exposed edge is brown, so I thinly slice it off and toss the brown part. I use avocado on sandwiches and have had them last for a week this way.
I rarely have leftover avocado - as I always eat the entire thing. Yummy! (But, if I ever do, I'll try all of these handy methods. Thanks!)
There's an avocado vender at the Ferry Building farmer's market/San Francisco, whose avocados, I swear, do not turn brown - not right away, anyway. I feel confident sticking a loosely wrapped half in the fridge and not worrying about scraping off a single millimeter of precious green stuff.
Not their Reeds, though. Those things are horrible.
Scoop out the flesh and freeze.They stay good forever. When you want to use them put it in the microwave and push the defrost button. Defrost for around 10-20 secs and avocado is good to go
eat the whole thing, the stomach is full of acids that keep avocado fresh. duh.
Well, I've never really had much of a problem with leaving the stone in one half and spreading lemon juice on it--usually that will keep an avocado fresh for days. I think the citric acid probably works just as well as the sulphuric acid as a preservative and does not leave your avocado tasting like a raw onion. If a millimeter does start to turn color I just cut it off.
I think waxed paper works well to, press it up against the cut side of the avocado, store in container. I put waxed paper directly on the surface of guac too.
Funny, but it seems I have often cut and onion and avocado and stored them together, and subconsciously was please it had lasted so long. I'll have to pay more attention.
Sweet! Thanks Dana V!!!
Love the onion idea! My husband and I love guacamole, but we always have to eat it all the first day! I'll try the chopped onion trick :) Thanks
Can't you just use the entire avocado in one go? I would hate to throw them out because they're no longer attractive.
Between myself and my two daughters, there would never be leftover avocado in our house. If it does happen, however, I will definitely try one of these tricks.
For me, the best way to ruin guacamole is to add onions to it. Raw onion overpowers the avocado. Same goes for garlic. The best guacamole has just four ingredients: avocado, fresh chopped tomato, cilantro, lemon juice. The only other ingredient I would ever add is salsa, if you want some extra bite.
Hmm--salsa usually has both onions and garlic, so that sort of cancels out your argument :).
I love a little bit of finely chopped onions and a good bit of garlic in my guacamole.
My roommate and I have a vow to have avocados in the refrigerator at all times. Same as most people, we can never keep them from getting dark. For guacamole we heard that keeping the pit in is supposed to keep it from browning, but it never has really worked. I'm excited to give this a try.
When I worked at a Mexican restaurant, we would cover our guac with lime juice and then plastic wrap until the next use.
Great info!
Another great way to preserve guacamole is to place a layer or tomatoes on top. The acidity from the tomatoes works the same as lime, plus it blocks air and light!
My dogs usually get any leftover avocado...
I have tried this a couple of times now. I have a 13 month old who often eats 1/4 of an avocado at a time for meals or snacks.
It works wonderfully well and, since I often have part of an onion in the fridge too, now I just use one less storage container!
For guacamole just put like two spoong of milk, it won't change the flavor and will make a creamier guacamole, also keeping it for getting brown
We've never had leftover avocado here!
I'm glad I found this! I just thought my avocados were goners once I cut them open. I'll try some of these remedies and see which one works the best for me.