The mango is a popular tropical fruit enjoyed worldwide for its sweet taste. Botanically, it is classified as a drupe, or stone fruit. This places it in the same category as other fleshy fruits that contain a single, hard-shelled seed, such as peaches, cherries, and olives. Drupes develop from the single ovary of a flower and are characterized by their distinct layered structure.
The Exocarp
The outermost layer of the mango is the skin, known botanically as the exocarp. This layer serves as a protective barrier, defending the fruit from environmental stressors and pests. The exocarp’s texture is typically smooth and can feel waxy to the touch. Its coloration is highly variable among different cultivars, ranging from green and yellow to shades of orange and red, though color is not always a definitive sign of ripeness.
Scattered across the exocarp are small, visible dots called lenticels. These pores facilitate gas exchange between the fruit and the atmosphere. While the skin is a source of nutrients, it also contains urushiol, the same compound found in poison ivy. For some individuals, contact with or ingestion of the skin can cause an allergic reaction known as contact dermatitis.
The Mesocarp
Beneath the skin lies the mesocarp, which is the succulent, edible flesh of the mango. The desirable taste is due to a high concentration of sugars, primarily sucrose and fructose, stored in this layer. The biological purpose of this sweet, energy-rich flesh is to attract animals, which consume the fruit and then disperse the seed in a new location.
The texture of the mesocarp can vary significantly from one mango variety to another. Some cultivars, like the Ataulfo, are known for their smooth, buttery consistency with minimal fiber. In contrast, other types can be quite fibrous, with stringy tissues running through the flesh. The color of the mesocarp is typically a vibrant golden-yellow or deep orange when the fruit is mature.
The Endocarp and Seed
At the center of the mango is the structure commonly referred to as the pit or stone. This pit is not a single entity but consists of two distinct parts: the endocarp and the seed. The endocarp is the hard, woody husk that directly encases the seed. This tough, fibrous layer protects the seed from physical damage and digestion.
The seed contains the embryo, which holds the genetic information for a new mango tree, and the cotyledons, which are the seed leaves that provide nourishment for the embryo during germination. While the endocarp is inedible and fibrous, the seed inside is the basis for the mango’s reproduction.