The green coffee bean looks something like a hard dried pea, split in half. If ground and brewed in this raw state, it would produce an undrinkable beverage that none of us would recognize as coffee. The act of roasting coffee forces water out of the green bean, sets off a transformation of some of the beans sugars into C02 gas, dries out and expands its woody parts, making the bean more porous and easier to grind. Most importantly, roasting of the green coffee bean caramelizes the sugars in the bean and transforms some into aromatic flavor oils and traces of volatile bitter acids.
Roasted coffee gets its wonderful aromatic character and flavor largely from the caramelized sugars and flavor oils in the bean. After roasting the bean becomes a protective package for the caramelized sugars and flavor oils, which nest in the tiny porous pockets of the beans interior, and sometimes the oils leach out (in the case of darker roasts) to coat the exterior of the bean with a fine oily layer. The carbon dioxide gas produced by some of the beans sugar during roasting continues leaching out of the bean afterwards in a process called degassing, which temporarily protects the volatile flavor oils from oxidation.
Coffee is at its peak 4 to 24 hours after roasting, after which time the volatile flavor oils begin to evaporate as the carbon dioxide gas seeping from the freshly-roasted bean dissipates. Two days after roasting, a good part of the aroma has become oxidized by the oxygen in the air, and a week later the taste is also diminished, and after two weeks the volatile aroma has largely vanished and the taste has lost some of its rich complexity. When you roast coffee, grind and drink it within 3 days for the ultimate in freshness and aroma.
Unless you live near a specialty coffee roaster that roasts beans on a weekly basis, you are not getting the freshest, most aromatic coffee. Even high quality coffee roasted by a national chain can be weeks (or months) out of the roaster before you finally buy it off the shelf. Worse, the date of the roast is rarely available to the consumer, so you usually are buying expensive gourmet coffee with one blind eye, without knowing when it was roasted.
Besides freshness, roasting your own specialty coffee saves money. Quality green beans sell for about half the price (or less) of already roasted specialty coffee, and green beans keep for at least two years if stored in a dry, well ventilated area.
Roasting your own green coffee beans is a little like brewing your own - you do it for freshness and flavor, the fascination of the process, to save money, and most importantly, for the satisfaction of drinking a truly fresh cup of coffee with all the volatile flavors intact To assist you in this pursuit, we offer the finest quality green beans that we personally sample before selling, and only sell coffee roasting equipment that we have exhaustively tested.