Coffee Beans

Coffee berries and their seeds undergo multi-step processing before they become the roasted coffee with which most Western consumers are familiar. First, coffee berries are picked, generally by hand. Then, the flesh of the berry is removed, usually by machine, and the seeds are dried and sorted. The seeds are then labeled green coffee beans.

The next step in the process is the roasting of the green coffee. Coffee is usually sold in a roasted state, and all coffee is roasted before being consumed. Coffee can be sold roasted by the supplier or it can be home roasted. The roasting process has a considerable degree of influence on the taste of the final product, creating the distinctive flavor of coffee from a bland bean, by changing the coffee bean both physically and chemically.

Physically, the bean decreases in weight as moisture is lost, but increases in volume, causing the bean to become less dense. When bean temperature reaches 200°C (392°F), the actual roasting begins. Different varieties and ages of beans differ in density and moisture content, causing them to roast at different rates. The density of the bean is important because it influences the strength of the coffee and requirements for packaging it.

During roasting, caramelization occurs as the intense heat breaks down starches in the bean, changing them to simple sugars which begin to brown, adding color to the bean. Sucrose is lost rapidly during the roasting process; in darker roasts, it may disappear entirely. As the bean roasts, aromatic oils, acids and caffeine weaken, changing the flavor. When the internal temperature of the bean reaches 205°C (400°F), other oils will start to develop.One of these oils is caffeol, created at about 200°C (392°F), which is largely responsible for coffee's aroma and flavor.

 

Given enough coffee, I could rule the world

 

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 smoother, because they have less fiber content and a more sugary flavor. Lighter roasts have more caffeine, resulting in a slight bitterness, and a stronger flavor from aromatic oils and acids which are destroyed by longer roasting times.

A small amount of chaff is produced during roasting from the skin left on the bean after processing. Chaff is usually removed from the beans by air movement, though a small amount is added to dark roast coffees to soak up oils on the beans. Decaffeination may also be part of the processing that coffee seeds undergo. Decaffeination is often done by processing companies, and the extracted caffeine is usually sold to the pharmaceutical industry.