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How to keep Guacomole from turning brown??

Bruin2 Dec 30, 2004 03:42 PM

I need to pre-make a substantial amount of Guacomole for a party but don't want it to turn ugly brown before I serve it. I would like to make it in the morning and then serve it in the late evening. Any suggestions on what to do? Does just sprinkling with lime before putting in fridge work? Or can I make it and freeze it and then thaw as needed? Or has anyone tried that powder Fresh Fruit? Thanks in advance.

  1. j
    jennyantepenultimate Dec 31, 2004 12:50 AM

    Since the troublesome part that turns brown is only the avocado, why not just pre-chop and mix the other ingredients for flavor blending and then cut up the avocado at the last minute before your guests arrive? The hard part about making guac is all the chopping so with that part done, smooshing up some avocados should go fairly quickly.

    Actually, I do this all the time when I make pico de gallo (garlic, onion, lime, jalapeno, tomatoes, salt) and my version of guacamole, which is just pico with avocado puree added. I like to chop by hand but a food processor will go just as well with the perk of letting the avocado "clean up" the bowl when you make the guac part after taking out some pico. Flavor and/or texture adjustments can be made with cumin and sour cream, if necessary.

    1. s
      sbp Dec 30, 2004 06:04 PM

      If you have a foodsaver, put it in a bag and vacuum out the oxygen.

      1. h
        Hugh Lipton Dec 30, 2004 05:05 PM

        Having previously been married to a Mexican-American lady I was taught by her mother that after I made the guacamole I should place the avocado pits back on top of the guacamole and then cover with either foil or plastic wrap until serving. I never suffered the turning brown. Maybe the guacamole thinks it is till inside the avocado because of the pits. Beats the heck out of me but works.

        8 Replies
        1. re: Hugh Lipton
          Val Dec 30, 2004 06:39 PM

          I agree with Hugh...put the avocado pit into the guac mixture...can't remember who did it, either Emeril or Bobby Flay, but it does work.

          1. re: Hugh Lipton
            snackish Dec 30, 2004 09:11 PM

            Our alliterative saying is "Put the pits in the pot".

            1. re: Hugh Lipton
              Reece Dec 30, 2004 10:58 PM

              This is definitely the tradition, but I think it's due to the surface-area coverage rather than any significant chemical reaction. In other words, the plastic wrap would do the job better.

              1. re: Hugh Lipton
                TP Jan 1, 2005 12:23 AM

                This is the #1 myth with guacamole turning brown - putting the pit in. Urban legend, old wive's tale, and so on.

                The turning is due to oxygen, so pit or no pit, the guac will turn. Another factor is the crop itself - season, location, growth, harvest, and so on.

                After making literally hundreds of cases (1 case = 40+ avocados) of guac, the best two things to lessen browning are:

                1. Cover the guacamole with TWO layers of plastic wrap. Bang your pan/bowl on table to get rid of any air bubbles. Then place one layer DIRECTLY on the guacamole skin, removing any visible air bubbles in surface. Then rewrap with plastic. It slows down browning, and only the surface will brown. When ready to use, simply scrape like 1/8" top layer to reveal the bright green guac underneath. This works like up to the day before.

                2. Citrus juice (lemon, lime, mix) will help also. Not only for flavor, but for preserving and less browning.

                You can also add a pinch of citric acid. Doesn't really affect taste (in small quantities).

                1. re: TP
                  Hugh Lipton Jan 2, 2005 09:35 AM

                  Myth huh? See link below.

                  Link: http://thepassionatecook.typepad.com/...

                  1. re: Hugh Lipton
                    FlyFish Jan 2, 2005 04:50 PM

                    Sorry, but this business of the avocado pit really is a myth, and no amount of anecdotal misinformation can change that. Harold McGee, in his second book (The Curious Cook), convincingly demonstrated that the pit only prevents browning of the guacamole immediately underneath it, which is consistent with the plastic film advice of most posters here. He also found - no surprise - that a light bulb would accomplish the same thing. He then goes on to discuss the differences in permeability to oxygen of the different plastic wraps, as another poster pointed out.

                    1. re: Hugh Lipton
                      TP Jan 2, 2005 08:05 PM

                      Myth, myth, and, oh, yes, myth.

                      If you can't listen to an expert on Food Chemistry like McGee, then why waste our time:


                      (At least this link is based on published works and tests, not some random website and recipes.

                    2. re: TP
                      Hugh Lipton Jan 2, 2005 09:38 AM

                      And, how about this one??? I'm done now!

                      Link: http://www.rutherfurd.net/cookbook/Di...

                  2. n
                    Neta Dec 30, 2004 04:47 PM

                    I've always found a couple tablespoons of warm water works well.

                    1. s
                      SteveT Dec 30, 2004 04:23 PM

                      All the posters got it right with the plastic wrap directly on the surface. Just one additional hint...since only the surface turns brown (not the entire container), you can stir in any brown surface to disburse it. The top 1/16 inch of brown mixed into 4" of green should result in a green mixture.

                      or you can perform 'quality control' on that top 1/16"

                      1. c
                        Christine Dec 30, 2004 04:02 PM

                        Don't freeze it once it's put together. The water will draw out of the vegetables and you'll have a soupy mess after it's thawed.

                        I actually do think that putting the pits back in helps a little, but the most important thing is to keep oxygen out. So be sure to put plastic wrap right on top of the guacamole, and work the air bubbles away with your hands (same idea as keeping a skin from forming on a pudding).

                        1 Reply
                        1. re: Christine
                          Reared on Home Cookin Jan 3, 2005 12:24 AM

                          Who would keep a skin from forming on top of a pudding? I'm flabbergasted. People will think you made them instant.

                        2. f
                          FlyFish Dec 30, 2004 04:01 PM

                          The browning is a chemical oxidation that results from contact with the oxygen in air. Citrus juice contains ascorbic acid (vitamin C), an antioxidant, that will help to prevent browning, which is why sprinkling lemon or lime juice over the surface will help. If you do that and also press a covering of plastic wrap down into the bowl so that it's in contact with the guacamole (i.e., not stretched across the top of the bowl), then refrigerate, you should be able to keep things green for a reasonably long time. You may need to dispose of the small amount of guacamole that will remain attached to the plastic when you remove it.

                          1. c
                            Chino Wayne Dec 30, 2004 03:58 PM

                            I would use lime, but also since the browning is probably from oxidation, try and press some plastic film (Saran wrap) right on to the guac so that air cannnot get to it.

                            2 Replies
                            1. re: Chino Wayne
                              gordon wing Dec 30, 2004 09:55 PM

                              Harold McGee agrees with you about using Saran Wrap. He has tested many of the plastic wraps and found that Saran Wrap is the most air tight - that's why it doesn't cling as well as some others. (Ever wonder why a wrapped onion still makes your fridge smell?...)
                              All the others will let some air in (albeit slowly) and since the OP wants to keep the guac for many hours, it may make a difference.
                              As you said, press the wrap directly onto the surface .... HMcGee also tested the avacado pit and found out that a light bulb worked just as well when substituted for the pit.....mmmmm.

                              1. re: gordon wing
                                Hugh Lipton Dec 30, 2004 10:15 PM

                                That certainly illuminates the question. Happy New Year

                            2. d
                              DanaB Dec 30, 2004 03:54 PM

                              In my experience, guacamole is best made shortly before serving if at all possible, because the longer it sits, the browner it will get. Lemon or lime juice over the top will help keep it from turning for a while but is not a cure all. Putting the pit in does *not* help in my experience, as whatever portion of the guacamole is touching air or surface of any kind is subject to browning (i.e. the portion next to the container wall will brown a bit the longer it sits). The only solution I've found is to scrape off or avoid the browned parts when serving.

                              I've never tried freezing fresh guacamole so don't know if that is an option.

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