Although all avocados may initially appear to be the same, there are three races of avocados to consider: West Indian, Guatemalan and Mexican. In addition to these three races there are also hybrids and many different varieties that vary in size, shape and even taste. Despite these differences, all avocados are made of the same basic parts.
The exocarp of an avocado is commonly referred to as the skin. Depending on the type of avocado, the skin color and thickness will vary. For example, Gwen avocados have green skin that is thick with a pebbled appearance, while Zutano avocados have thin skin that is yellow-green and shiny. The exocarp of certain avocados may also change in appearance as the fruit ripens. Hass avocados start with green skin that darkens to a purple-black color when ripe. The Fuerte avocado, which has thin green skin, does not change in appearance when ripe.
The mesocarp is also known as the flesh of the avocado, and this is the edible and most abundant part of the fruit. The flesh of the fruit also varies in appearance depending on the variety of avocado. The Bacon variety of avocado has flesh that is a greenish-yellow, while the Pinkerton variety has pale, creamy green flesh. The Zutano avocado has flesh that is light in texture with a pale green color.
The endocarp is the thin inner layer of the avocado that is found between the flesh of the avocado and its seed. It is often difficult to differentiate the endocarp from the flesh of the avocado fruit. When the seed is ripe, the endocarp may appear to be a film over it, giving it a frosty or whitish appearance.
At the center of the avocado is its seed. It is the seed that makes the avocado a fruit as opposed to a vegetable and it can vary in size from small to large. The variations in seed size are dependent on the type of avocado. The Pinkerton, which is a winter variety avocado, has a small seed at its core. Reed avocados, a summer variety, and Lamb Hass, which is a California summer variety, both have medium seeds. The mid-winter variety Bacon avocado has a medium to large seed.