Coffee roasting

Roasting coffee transforms the chemical and physical properties of green coffee beans into roasted coffee products. The roasting process is what produces the characteristic flavor of coffee by causing the green coffee beans to expand and to change in color, taste, smell, and density. Unroasted beans contain similar acids, protein, and caffeine as those that have been roasted, but lack the taste. Heat must be applied for the Maillard and other chemical reactions to occur. As green coffee is more stable than roasted, the roasting process tends to take place close to where it will be consumed. This reduces the time that roasted coffee spends in distribution, giving the consumer a longer shelf life. The vast majority of coffee is roasted commercially on a large scale, but some coffee drinkers roast coffee at home in order to have more control over the freshness and flavor profile of the beans. Processing of coffee is the method converting the raw fruit of the coffee plant into the coffee. The cherry has the fruit or pulp removed leaving the seed or bean which is then dried. While all green coffee is processed, the method that is used varies and can have a significant effect on the flavor of roasted and brewed coffee. A coffee plant usually starts to produce flowers 3Ц4 years after it is planted,[1] and it is from these flowers that the fruits of the plant (commonly known as coffee cherries) appear, with the first useful harvest possible around 5 years after planting. The cherries ripen around eight months after the emergence of the flower, by changing color from green to red, and it is at this time that they should be harvested.[2] In most coffee-growing countries, there is one major harvest a year; though in countries like Colombia, where there are two flowerings a year, there is a main and secondary crop.[3] In most countries, the

offee crop is picked by hand, a labor-intensive and difficult process, though in places like Brazil, where the landscape is relatively flat and the coffee fields immense, the process has been mechanized.[3] Whether picked by hand or by machine, all coffee is harvested in one of two ways: Strip Picked: The entire crop is harvested at one time. This can either be done by machine or by hand. In either case, all of the cherries are stripped off the branch at one time. Selectively Picked: Only the ripe cherries are harvested and they are picked individually by hand. Pickers rotate among the trees every 8 Ц 10 days, choosing only the cherries which are at the peak of ripeness. Because this kind of harvest is labor intensive, and thus more costly, it is used primarily to harvest the finer arabica beans.[3] Workers sorting and pulping coffee beans in Guatemala The laborers who pick coffee by hand receive payment by the basketful. As of 2003, payment per basket is between US$2.00 to $10 with the overwhelming majority of the laborers receiving payment at the lower end. An experienced coffee picker can collect up to 6-7 baskets a day. Depending on the grower, coffee pickers are sometimes specifically instructed to not pick green coffee berries since the seeds in the berries are not fully formed or mature. This discernment typically only occurs with growers who harvest for higher end/specialty coffee where the pickers are paid better for their labor. Mixes of green and red berries, or just green berries, are used to produce cheaper mass consumer coffee beans, which are characterized by a displeasingly bitter/astringent flavor and a sharp odor. Red berries, with their higher aromatic oil and lower organic acid content, are more fragrant, smooth, and mellow. As such, coffee picking is one of the most important stages in coffee production.