Coffee Processing and Coffee Roasting

Coffee processing and coffee roasting  undergo several stages of development before they become the coffee with which most Western consumers are familiar with.

First, the coffee beans are picked, usually by hand. Then, the flesh is removed from the slots, most often by machine, and the seed-beans are fermented usually called to remove the viscous layer of mucilage still present on the beans. When the fermentation is complete, the beans are washed with large amounts of fresh water to remove residual fermentation, generating huge quantities of highly polluted coffee wastewater. Finally, the seeds are dried and sorted and labeled as green coffee beans.

The next step in coffee processing is coffee roasting. Coffee is usually sold already roasted and all coffee is roasted all before it is consumed. It can be sold by the supplier roasted, or the coffee roasting can be  be done at home.  The coffee roasting affects the taste of the drink by changing the coffee bean both physically and chemically. The bean decreases in weight as the water is lost, but increases in volume, and may become less dense. The density of the bean also affects the strength coffee and packaging requirements. Coffee roasting begins when the temperature inside the bean reaches 200 ° C (392 ° F), although different kinds of beans differ in moisture and density and thus roast at different rates. 

During the coffee roasting, caramelisation occurs as intense heat breaks down Starches in the grain, changing them to  simple sugars that begin to brown and change the color of the bean.  Sucrose is rapidly lost during coffee roasting and could disappear entirely in dark roasts. During coffee roasting, aromatic oils, acids,  and caffeine weaken, changing the flavor.  One of these oils is caffeol created approximately 200 ° C (392 ° F), which is largely responsible for the coffee aroma and flavor.

Depending on the color of the roasted beans, they will be labeled as light, cinnamon, medium, high, city, full city, French, or Italian roast.^[

Darker roasts are generally smooth, because they have less fiber and more of a sweet flavor. Lighter roasts have more caffeine, resulting in a slight bitterness and a deepening of the flavor of aromatic oils and acids destroyed by more roasting time.  A small amount of chaff is produced during the coffee process and coffee roasting period and normally left on after treatment. 

Chaff is often times removed from the beans by air movement, although a small amount is added to dark roast coffees to soak up oils on the beans. Decaffeination is also be part of the coffee processing that coffee beans undergo. Beans are decaffeinated when they are still green. Many methods can remove caffeine from coffee, but all involve either soaking beans in hot water or steaming them, then using a solvent  to dissolve caffeine-containing oils.

Decaffeination is often done by coffee processing companies, and the extracted caffeine is usually sold to the pharmaceutical industry.  Chaff is usually withdrawn from circulation by air beans, but a small amount is added to the dark roast coffees to absorb the oil on the beans. The seeds are decaffeinated when they are still green. Many methods can remove caffeine from coffee, but all involve either soaking the beans in hot water or steam, and then using a solvent to dissolve oils containing caffeine.  The decaffeination is often done by the processing companies and the extracted caffeine is generally sold in the pharmaceutical industry.