My friend was telling me about a habit in the Spanish culture (I'm not sure if it's done elsewhere as well) of leaving the avocado seed inside when making guacamole. The claim is that if you leave the seed inside the guacamole, something in the seed prevents the guacamole from browning.

I'm a little skeptical - I thought that the browning was due to oxidization. If that's the case, then I don't see how a seed could help in preventing oxidization. Am I missing something? Is this true, or just a myth?

2 Answers 2


You're correct - it's a myth, as is adding something acidic to it like lemon juice--see explanation here. As you said, what causes it to brown is the oxidation, and that's just exposure to the air. If you wrap a cut avocado (or guacamole) in plastic wrap so there's no air space between the wrap and the avocado, then it will stay green longer than areas where air is getting to it.

  • Yes, it seems logical. But do you have any references? You mentioned that adding something acidic is also a myth - this answer seems to imply the opposite.
    – voithos
    Jun 21, 2012 at 1:09
  • Also, I found a link that seems to provide evidence that the seed thing is a myth. It also seems to indicate that adding something acidic does help...?
    – voithos
    Jun 21, 2012 at 1:10
  • 3
    The fact that exposure to air causes browning doesn't mean that adding an acid won't inhibit it. It definitely does help, just like it does with cut fruit. You're right about the pit, though - the only part it stops from browning is the part it's in contact with instead of air.
    – Cascabel
    Jun 21, 2012 at 1:11
  • 1
    Ray's answer is right. My source for this one is the Serious Eats blog, and their resident food scientist Kenji Lopez (scroll down to "On Browning" and go from there: seriouseats.com/2012/01/…
    – franko
    Jun 21, 2012 at 13:39
  • 2
    I have asked about this on Skeptics, and it appears the answer is, that citric acid can be beneficial, or detrimental, depending on the variety of avocados used. But Ascorbic acid should always work.
    – Flimzy
    Jul 7, 2012 at 18:03

This is not an old wives tale. Everyone knows that oxygen turns the guacamole brown. I have read everywhere that some chef did an experiment with a light bulb and the guacamole did not turn brown around the light bulb thus he concluded that it worked the same way as the pit..Wrong! If people would actually tried the pit trick instead of reading some crackpot ideas they would see that the a couple pits in the bottom keep it from turning brown. Oxalic acid is in the pits and absorbs the oxygen which turns the guacamole brown.

  • If you actually try this, you'll see that it turns brown everywhere that's exposed to air, and it's just the part in contact with the pit that stays green.
    – Cascabel
    May 29, 2015 at 5:39
  • Similarly, if you press plastic wrap into the top of the guacamole, it doesn't brown.
    – Catija
    May 29, 2015 at 15:25

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.