Avocados are a high-protein food that is very common in Mexican and Spanish dishes. It is used as a dip to make guacamole and it can be cut in slices to put on a sandwich or in pita bread.
When avocados are at their peek ripeness, they are creamy with an almost buttery taste. Once they begin to turn brown, they lose their fresh taste and appeal. (See Reference 1)
Avocados turn brown for two reasons, if they are bumped or dropped, they can bruise, and when they are cut open and oxygen hits the "meat" they begin to oxidize and thus turn brown. (See Resource 1)
Once an avocado is sliced open, it will begin to turn brown within hours. When making any recipe that includes avocados, make sure it is something that will be consumed within a few hours. (See Resource 1)
It is not a good idea to eat avocados once they turn brown since they will not taste as well and the browner they get, they can begin to smell rancid. (See Resource 1)
When making guacamole, after you have mixed all your ingredients, put one of the avocado seeds back in with the guacamole, this will keep it greener longer. Lime squeezed in the guacamole will also keep it fresher. (See Resource 1)