In order to avoid and prevent avacados from browning due to oxidation, simply cut the avacado in half. After cutting the avacado in half, remove the pit and place the cut side down in a bowl. In the bowl, you should have a preparation of 1 tbs of lemon or lime juice and 1 cup of water. The citric acid in the lemon lime juice will prevent the avacado from browning. The skin that remains on the uncut side will protect the remaining flesh from discolorization. Cover the avacado and bowl with plastic wrap and refrigerate up to 2 day until ready to use. If using an entire avacado, but not immediately, sprinkle slices with lemon or lime juice and enjoy.