Why does leaving the seed in the avocado make it last longer and not turn brown?
Same with leaving it in your guacomole, if you prepare it in advance if you leave the seed in it it wont turn brown either.
Just a WAG here. The avocado’s pulp is geared towards protecting the seed, speeding it on its way to make another avocado tree, attracting an animal of some kind that will pick up the fruit and take the seed somewhere else where it can grow. So once the seed is gone, the pulp knows its job is over and it throws in the towel and quietly dissolves into brown mush.
Another WAG (with a bit of a possible chemical mechanism behind it)
I know that putting lemon juice on the guacamole will also slow the browning. I think it is much like the browning of apples which is
WAG: because of oxidation??
I think that the acid in the lemon juice retards the oxidation by being oxidized itself. ie, the free H+ ions in the acid accept the e-'s that would normally do something or other (at this point my knowledge of acid/base and electrochemistry runs out).
Perhaps the same kind of exchange occurs across the seed to help it start growing. When the pulp is exposed to air, it transports electrons to or from the seed, which helps catalyze some internal process. As soon as the seed is no longer in contact with the pulp, the pulp itself is oxidized.
http://www.leskincaid.com/food/recipes/Avocado%20turning%20brown.htm
It’s a myth. DDG is correct that oxidation is what is causing the browning - all the pit does is keep air from reaching part of the avocado or guacamole. Lemon juice works because it has vitamin C or ascorbic acid, which counteracts the oxidation.
Well color me silly…it was an old wives tale all along. Hmmm.
I wonder if anyone has been able to isolate the effects of lemon juice to create a product that keeps food from turning color without the lemon taste. That would be really cool. A safe, natural product that you can spray on without the taste of the lemon. If they have it I am interested.
Any thoughts?
There is a product called “fruit fresh” that is used to keep things like peach and apple preserves from getting too brown. I’m not sure if it has any flavor of its own.
And Fruit Fresh is straight Vitamin C(ascorbic acid). But probably easier to find than powdered ascorbic acid.