Mesocarp

The mesocarp is the middle layer of the pericarp, the ovary wall that encloses the seeds in flowering plants. It lies between the outer exocarp (skin) and the inner endocarp (often the stone or seed coat). In many fleshy fruits, the mesocarp forms the edible portion.

The morphology of the mesocarp varies by species. In drupes such as peaches and mangoes, it is the fleshy, juicy tissue that people typically eat. In coconut, the mesocarp becomes the fibrous husk surrounding the shell. In citrus fruits, the mesocarp corresponds to the white spongy albedo between the rind and the juice sacs. In cacao, the white mucilaginous pulp around the seeds is derived from the mesocarp. In some berries, the pericarp is largely fleshy and includes significant mesocarp tissue as well.

Development and composition: the mesocarp develops from the ovary wall during fruit formation and is often rich in parenchyma cells. It commonly stores sugars, acids, pigments, and aromatic compounds, contributing to fruit flavor, texture, and nutritional value. Depending on the species, the mesocarp can remain soft and succulent or become fibrous or woody as the fruit matures.

In botanical terminology, the mesocarp is one of the three main layers of the pericarp, along with the exocarp (outer skin) and endocarp (inner layer around the seed). Its structure and function help determine the edible characteristics of many fruits.