Most of the coffee you buy from a grocery store is already roasted or roasted and ground. This is a convenience that coffee companies do for consumers so that consumers do not have to roast their own coffee every morning before they brew it or grind and brew it. Yet, you pay for this convenience, so maybe you would want to learn how to roast your own coffee beans. Here is how local coffee roasters do it, and how you can too.
Buy Green Coffee Beans
Green coffee beans are plucked from the coffee cherry. Despite the fact that the beans are called green, they are not really green at all. They are more of a dirty, off-white color. They are referred to as green because roasted beans are varying shades of brown and black. It is much in the same way as olive oil is referred to as "extra virgin" versus "cold-pressed." The extra virgin olive oil is taken straight from the olives and left unprocessed. So, too, are the green coffee beans.
You can buy green coffee beans from growers in various countries. The beans themselves have been dried in the sun, and will be hard. They are ready for roasting when they arrive at the coffee shop (or your doorstep). The coffee shops that roast their own buy green coffee beans by the fifty- or hundred-pound bag and store them in cool, dry places where they will not begin to grow shoots before they can be roasted.
Into the Roaster
Coffee houses have custom-made bean roasters into which the bags of green coffee beans are poured. They set the timers on the machines, and the machines heat up to a specific temperature and roast the beans for that time. The darker the roast, the longer the beans sit in these roasters and are stirred to prevent burning. The varying levels of roasting gives you a lighter or darker flavor of coffee.
At home, you should probably start with the smallest bag of beans possible so that you do not have to spend an entire day roasting beans to prevent coffee tree seedlings. Anything that cooks at a really high temperature, such as your oven, a steam popcorn popper, etc., works. In your oven, lay the beans out on a cookie sheet and bake them at a high temperature for ten minutes for lighter beans, and up to twenty minutes for darker roasts. Use the same amount of time if you put the beans in any other kind of machine.
Cool and Bag the Beans
The coffee shops have to carefully remove the roasted beans from their roasters and let the beans cool. Then the beans are bagged and sealed. At home, you have to do the same thing. Just make sure your bags are airtight to prevent the beans from becoming stale.