For many, coffee’s journey begins with a roasted “bean” and ends in a cup. This common term often prompts a question: does the coffee plant truly produce beans? What we brew is actually the seed of a fruit. Understanding this botanical distinction reveals the intricate process that transforms a coffee plant’s fruit into the familiar form we recognize.
What is a Coffee “Bean”?
What we call a coffee “bean” is botanically a seed, found inside the fruit of the coffee plant, known as a coffee cherry. The coffee cherry is classified as a “drupe” or “stone fruit,” similar to a peach, meaning it has a fleshy outer part surrounding a hardened shell with a seed inside. Typically, each coffee cherry contains two seeds, which lie flat against each other. About 5% to 10% of coffee cherries, however, contain only one rounded seed, known as a peaberry.
The coffee cherry has several distinct layers protecting these seeds. The outermost layer is the exocarp, or skin, which changes color from green to red, yellow, orange, or purple as it ripens. Beneath the skin lies the mesocarp, a fleshy pulp rich in sugars. Encasing the seeds is a sticky, gelatinous layer called mucilage, followed by the parchment, a thin, protective shell. The innermost layer, adhering to the seed, is the silverskin, which often flakes off during roasting.
From Flower to “Bean”: The Production Process
The journey of a coffee “bean” begins with the coffee plant producing delicate, fragrant white flowers. These blossoms typically appear once or twice a year after a rainy season and are crucial for fruit development. After pollination, these flowers give way to small, green coffee cherries. These cherries gradually ripen over several months, usually taking about seven to eight months from blossom to a fully ripe cherry.
Harvesting methods vary, with hand-picking common for higher quality coffee, where only the ripe cherries are selected. Once harvested, coffee cherries must be processed quickly to extract the seeds.
Two primary methods are used for initial processing: the wet (washed) method and the dry (natural) method. In the wet method, the outer skin and pulp of the cherry are mechanically removed, and the remaining mucilage is broken down through fermentation before the seeds are washed and dried. The dry method involves spreading whole coffee cherries in the sun to dry for several weeks, after which the dried outer layers are removed from the seeds. These extracted, dried green seeds are what will eventually be roasted to become the coffee “beans” we consume.