The familiar coffee bean is actually the seed found inside a small, often red, berry-like fruit known as a coffee cherry. This botanical fact challenges common perceptions, as coffee is typically associated with roasted seeds rather than fresh produce. Understanding this distinction provides insight into the origins of one of the world’s most popular beverages.
Botanical Classification of a Fruit
Botanically, a fruit is the mature ovary of a flowering plant that encloses a seed or seeds. This definition differs significantly from the culinary understanding of fruit, which often focuses on sweet, fleshy produce. True fruits develop from the flower’s ovary and contain the plant’s seeds, serving as a means of seed dispersal.
For example, items like tomatoes, cucumbers, and bell peppers are botanically classified as fruits because they originate from the flower’s ovary and contain seeds, even though they are commonly used as vegetables in cooking. Other examples include eggplants and squash.
The Coffee Cherry Unveiled
The coffee plant produces small, round fruits called coffee cherries. These cherries typically transition from green to a vibrant red, yellow, or even purple when ripe, depending on the coffee variety. Each cherry usually contains two seeds, which are the “coffee beans” we recognize.
The coffee cherry’s structure includes several distinct layers. The outermost skin is the exocarp, while beneath it lies the pulpy middle layer known as the mesocarp, which can be sweet and edible. Encasing the seeds is a papery layer called the endocarp, often referred to as parchment. Inside this parchment, each seed is further covered by a thin membrane known as silver skin.
From Cherry to Bean: The Journey of Coffee
After harvesting, the coffee seeds are extracted from the cherries through various processing methods. These methods separate the valuable seeds from the surrounding fruit layers. The two primary approaches are dry processing and wet processing.
Dry processing, an older method, involves drying the whole coffee cherries on large surfaces, such as patios, for several weeks. During this time, the fruit dries around the seeds, which are then mechanically removed. Wet processing, conversely, removes the fruit layers immediately after harvest by first pulping the cherries to strip the skin and pulp, then fermenting and washing the seeds to remove any remaining sticky mucilage.