The Process of Producing Coffee
Coffee is one of the world’s most famous beverages, as it is consumed around the globe. The process of coffee production, from seed to consumer, entails several steps. Coffee beans, essentially seeds, must undergo drying, roasting, and grinding before brewing into the beloved beverage.
Coffee seeds, known as unroasted coffee beans, are grown in rows shaded by excessive sunlight. Fresh seeds typically germinate within approximately two and a half months after planting, although older seeds may take up to six months to sprout. Coffee plants should ideally be cultivated in hilly regions with nitrogen-rich volcanic soil for optimal growth.
Elevation plays a crucial role in coffee cultivation. The arabica species thrives at higher altitudes, whereas the robusta species is typically grown at lower elevations or sea level. Additionally, coffee plants have specific rainfall requirements. A distinct wet season for cultivation and a dry season for harvesting is crucial.
Whether by machine or human hands, coffee is harvested through one of two methods: strip picking or selective picking. The strip-picking method involves removing cherries from the branch, which can be done manually or with a machine. When employing selective picking, only the red cherries are harvested, leaving the green ones to mature further.
After the harvest, coffee cherries undergo immediate processing to prevent spoilage. Two primary methods are employed based on resources and location: the dry and wet methods. The dry method, known as unwashed or natural processing, is commonly used in areas with limited water access and by small-scale farms. Cherries are spread on drying beds, exposed to the sun for 15 to 20 days, regularly turned, and covered at night to prevent moisture absorption. The wet method involves washing and sorting cherries before pulping them to remove the skin.
Next, the mucilage-coated beans ferment in large tanks with added enzymes to dissolve the sticky substance. After approximately 24 hours, beans are repeatedly washed to eliminate residue. These beans are sun-dried for a day or two before being sorted into different grades.
The coffee milling process involves several steps, including preparing dried beans for market. Hulling removes the dried husk layers (exocarp, mesocarp, and endocarp) from parchment coffee beans. Polishing eliminates sliver skin that may remain after hulling. Polished beans are considered higher quality but show little difference in content compared to unpolished beans.
Grading involves sorting beans based on size, weight, color consistency, and flaws. Initially done by hand, the process can take hours. A more efficient method uses pneumatic sorting by air jet to separate light and heavy beans. Beans are also sized through screens on a scale of one to ten. Only the finest beans are graded as high quality.
Coffee roasting is the pivotal process that transforms green coffee beans into the aromatic brown beans we love. Whenever feasible, the roasting process occurs near the consumer to maintain freshness. Beans begin to deteriorate in quality as soon as they are roasted. It’s conducted at about 550 degrees Fahrenheit, with the beans continuously turned to prevent burning. Initially, the beans dry and turn yellow, emitting a roasting aroma. When the beans reach about 400 degrees Fahrenheit, a first crack occurs, causing the beans to double in size and become light brown.
The beans turn medium brown as the temperature rises, releasing a fragrant oil called caffeol. This pyrolysis stage is crucial, imparting the aroma and flavor to coffee. Beans can be stopped at this stage for a light or medium roast or continue for a darker roast. Around 440 degrees Fahrenheit, a second crack signals the start of the second pyrolysis, resulting in dark brown, oily beans. After roasting, the beans are rapidly cooled with water.
After roasting, coffee beans are carefully packaged to retain freshness and flavor. This packaging comes in different types, such as whole bean, ground, or single-serve pods, often sealed in vacuum bags to shield the beans from air and light. Subsequently, the distributed coffee reaches local cafes, retail stores, and consumers. It can journey far from coffee-producing nations to reach regions known for their love of coffee.
Source: robjtolley
