Ensuring Freshness - Roasting at Home

by Don Holly

At the turn of the century, roasting coffee at home was as common as scrambling eggs, and special pans that fit into your Franklin-style wood burning stove were readily available for this purpose. Industrialization brought consolidation of roasters, and canned, roasted and ground coffee appeared in the marketplace. Eventually everyone forgot not only how to roast coffee but, even worse, what freshly roasted coffee tasted like. The growth of the specialty coffee industry over the last 15 years has largely been based upon the rebirth of regional and local roasters, and it is about time that coffee fanatics rediscover the art of roasting coffee at home.

Roasting coffee competently is no more complicated than making a good omelet. Sure, it takes practice, but after a few initially frustrating (but interesting) trial runs you will begin to produce something that is infinitely more satisfying than anything you could ever find in a can. Even with the relatively crude implements (relative to the more controllable commercial roasting machines available to the professional) in your home, you will be able to create custom roasts and blends that will be ultimately enjoyable. After all, freshly roasted coffee prepared by an amateur is still ten times better than stale coffee roasted by a professional.

What is fresh? At the Specialty Coffee Association of America we define fresh-roasted coffee as coffee that has been roasted within the last three to seven days. Coffee requires the first three days after roasting to de-gas and take on its full flavor profile, much like a good red wine needs to breathe before all of its character comes alive. After seven days the coffee has decomposed to a point where it no longer can be called "fresh." Many of its aromatic properties have degraded and the coffee seems to have lost its "spark." Storing the coffee in an opaque, airtight container at room temperature keeps it from staling more rapidly, but your senses should not be fooled by the claims of roasters who say their packaging keeps the coffee "fresh" beyond a week. It is not true; they only say that because they are unable to get it to you more quickly. This, of course, is the big argument for roasting at home.

So, how do you do it? Roasting is the application of dry heat. We are used to roasting chicken or even vegetables, but coffee beans require a different application of heat because they are small, dense objects. The best roast profile is usually a fairly low temperature, about 300 F. Roast the beans at this temperature until they are uniformly heated throughout, and then increase the temperature to about 400 F until the development of the beans reaches the desired point. It is important that the beans are constantly stirred during roasting so that they develop evenly. When the beans reach the desired darkness, cool them quickly or they will continue to roast in their own heat energy.

I recommend two methods for roasting at home. The method that requires the least capital investment is roasting the beans in a pan on the top of a stove. Use a heavy saute pan that can distribute high heat evenly. Put only as much green coffee in the pan as will cover three quarters of the bottom at a thickness of one bean. Start at a medium high flame or burner setting, stirring the beans with a wooden spatula or shaking the pan enough so that the beans turn over and mix regularly. They will start to loose their green color as the chlorophyll heats, and about the time that they are golden-beige you can turn up the heat to about three quarters flame. As they turn brown the beans will start popping. This is called the "first crack," although it really sounds more like a pop. You will also notice that a paper like substance, referred to as "chaff," will be shed by the beans. This chaff can float away and make a bit of a mess in your kitchen, but otherwise it is fairly harmless (we will discuss later how to separate the chaff from the beans). As the beans darken, they will begin to smoke, and if you like a really dark roast, you could set off your fire alarm if you don't turn on an exhaust fan.

How dark do you roast? That is very much a matter of preference, similar to how spicy you like your food. Some roasters will swear that every coffee, based on its individual character, has a "best" roast. For example, they may say those coffees that have "brightness" will not exhibit that quality if roasted too dark or coffees with heavy body may taste best at a medium-dark or darker roast. A "second crack," that does sound like a crackling of the beans, begins at the medium-dark to dark phase. Like any discovery in cooking, the best advice is to experiment with any given coffee and a variety of roasting profiles: more heat, less heat, longer roasting times, etc., tasting the difference that it makes to the finished product and forming your own opinion of what you like best.

The second recommended method for home roasting, and the one I prefer, requires an air popcorn popper. Several manufacturers make them, and every model I have tried works equally well. Because the chaff gets blown out fairly readily with an air popper, my wife likes me to roast out on the patio, which also makes it unnecessary to take the battery out of the smoke alarm. Remove the attendant hood from the popper and plug the popper in, giving the chamber half a minute to heat up. Pour a couple of ounces of green beans directly into the chamber. The beans should start to spin around in the bottom of the chamber, stirred automatically by the air popper's fan. Use the maximum number of beans that the chamber will hold up to the point that the beans just barely stir at the beginning of the roast. As the beans are dried out by the heat of the popper, they will also lighten up and expand, rotating more quickly and actually jumping around fairly vigorously in the chamber. I like to keep the chamber uncovered to keep the heat down until the beans start to turn light brown. Then I balance a stainless steel cover loosely over the top which effectively increases the heat during the second phase of roasting. By smelling, listening and every once in a while lifting the cover and looking at the beans, you can judge when they are done to your preference.

When the beans have reached their desired doneness, dump them into a metal colander or wire sieve and blow on them or place them next to a fan. By throwing them into the air a little bit, like farmers used to do with their wheat, you can separate any remaining chaff as well as cool them faster. It will take five to seven minutes to roast, and another three to five minutes to cool. Finally, seal them in a mason jar or similar container and let them sit for three days before brewing.

Home roasting is certainly not for everybody, and if there is a good local roaster nearby there may be little reason to do so because their equipment and professional skill can probably do better than you can at home. But just like the growth of home beer brewing has enhanced rather than replaced the success of local brew pubs, your experiments in home roasting will yield a greater understanding and appreciation of this magical product we call coffee. Have fun!

Don Holly Don Holly is administrative director of the Specialty Coffee Association of America in Long Beach, CA. He can be reached at 562.624.4100 or dholly@scaa.org


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