There are four categories of roasting coffee; light, medium, medium-dark, and dark. Unroasted coffee beans come green and depending on the roasting will determine the category which the bean will be become. Flavor of bean is determined by soil, altitude and weather conditions where it is grown. Coffee beans come from the famous regions of Hawaiian Kona, Jamaican Blue Mountains, Java, and Kenya.
In order to transform the green coffee bean into a roasted coffee product, heat needs to be applied for the chemical reaction and the physical properties to be changed. A coffee roasting machine is needed to start the roasting process. There are two types of roasting machines; which are the durm and the hot-air.They are used to heat the bean and change its properties.
As the bean absorbs the heat, the color shifts to yellow to the darker shades of brown. At the later stages of roasting, oils appear on the surface and the beans lose water and increases in its size. As the heat continues with the roasting, the bean will be changed to a darkened stage until the roasters use a mass temperature gauge to determine color, smell, and sound to monitor roasting process. Roasters listen for the crackling sounds and at the first crack that will mark the beginning of light roasts. At the second crack stage, that is when it becomes a medium roast. This is a dividing point between medium and dark roast.
The lighter the roast will exhibit more of its original flavor with the bean having higher acidity and no roasted flavor taste. Medium roasts are sweeter and more balanced with smoother taste and more body. Full roast have a somewhat spicy and heavier body with the aroma and the flavor becoming more evident. Double roast has a smokey-sweet, light bodied flavor, but a quite intense flavor. At the darkest stages of roasting, the “roast flavor” is so dominant that it is difficult to distinguish the origin of the beans used in the roast.
Coffee Roasting emits carbon dioxide so a preservation technique is needed.The optimal shelf life is about 2 weeks and ground coffee about 15 minutes. Coffee beans are placed in vacuum packing cans or vacuum sealed in foil bags with pressure-relief valves on bags. Roasted whole coffee beans can be considered fresh up to one month if kept cool. Freezing and refrigeration retards the staling process. When coffee is ground, it is best to be used immediately.
Article Source: https://EzineArticles.com/expert/Sarah_Conte/1308193
Article Source: http://EzineArticles.com/7032023