Implovator Sometimes innovating gets your hands dirty

Home Roasting Coffee

I originally guest wrote this piece for The Frugal Hostess.

Home Roasting Coffee

A few weeks ago, a friend in the office shared something really remarkable with me. He shared a cup of coffee, freshly brewed in his French press. I've been a coffee drinker all of my life, but I quit a year ago as part of a series of diet changes. I mistakenly thought my heavy caffeine intake was causing my energy crashes throughout the day. Come to find out, it was the excessive use of highly refined sugar.

Standard equipment for the bread machine / heat gun (BMHG) method.

My friend re-introduced me to coffee in a big way. It was the first time that I had coffee from a French press, although that alone didn't account for how amazing it tasted. That kind of flavor is only accomplished by high-quality, non-blended coffee beans that are roasted a few days before and ground that morning. My friend is a home coffee roaster.

A Lost Tradition

Buying your coffee roasted and ground is a relatively new trend that emerged in the 20th century. Until then, people often bought their beans green and roasted them at home since green beans store dry for months. Eventually, neighborhood roasters starting taking over the roasting chores for urbanites. It really wasn't until breakthroughs in packaging that people were later able to buy reasonably fresh coffee that was roasted, ground, and shipped to their local corner markets.

Even though the neighborhood roasters were being pushed out, coffee shops still survived. Then with the explosion of Starbucks, Americans were re-introduced to good[-ish] coffee. It wasn't the quality of their signature Arabica beans that won our hearths though. It was their mass marketing and fancy coffee drinks. Starbucks provides Americans with a wealth of flavor through different brewing techniques, added flavorings, and liberal use of sweeteners.

It's a real shame too, because all of these contrivances actually mask the wonderful flavors in good, fresh coffee. These are flavors that we simply aren't experiencing, because we're buying generic blends roasted months ago and packaged into bags with one-way valves to let CO2 out and prevent fresh air from oxidizing the coffee.

Thanks in large part to the Internet, the tradition of home roasting is being resurrected. It's incredibly easy, very fast, and more rewarding than you can imagine.

How Is it Done?

There are numerous home roasting appliances available, but they're all expensive and they're all slow. My friend uses a popcorn air-popper, and it works really well. Unfortunately, the newer designs have a simple metal screen at the bottom that allows the hot air to flow in to the cooking chamber. This does little to circulate the beans, and so you have to stir them too.

Air poppers are not the only device that can be multi-purposed to roast coffee. Alton Brown would be seriously proud of the Internet home roasting community. They use everything from pans on a stove-top to dog dishes. My research led me to the method that seems to be the most advantageous: the bread machine / heat gun method.

WARNING! Pretty much any re-purposed setup that rapidly roasts coffee is going to cause some smoke, lots of light and fluffy chaff, and some strong aromas. I should probably state that there's a fire hazard, so please be careful. It's not at all recommended that you do this inside. Maybe I better go on record by stating the following: I do not recommend that anyone try this at home at all. This is for illustration purposes only and represents what I do in the privacy of my own backyard...with a fire extinguisher.

My First Attempt...Poor Dogs

I already had a bread machine and heat gun at home, so I decided to order some beans. I use Sweet Maria's. They have a wonderful selection of delicious beans. They get their beans from responsible farms that they personally visit often to ensure that they meet their criteria. The site is also a great source for home roasting supplies and information. I highly recommend that you stop there next after reading [and commenting on] this.

My bread machine is actually a loaner from a friend. It's design has a large hole in the bottom, which doesn't work well for removing the pan and pouring the hot beans into the colander for cooling. I poured my green beans in, readied my heat gun, and turned the bread machine on the dough cycle as you don't actually want the bread machine's heating element going.

The bread machine happily stirred the beans as I aimed the heat gun down into the pan. The beans started to heat up, but then the little mixing arm on the bread machine started to slide off the top. It seems the resistance of the beans was not enough to keep the arm from being pushed off. I thought I was going to lose my first batch of beans. Then I remembered the dog bowl technique.

I quickly cleaned out my dogs' ceramic water bowl, transferred the beans, and started stirring them by hand. Amazingly, it turned out really well. The bowl got incredibly hot, and I actually broke it when I dropped it a mere two inches into the sink later. But all in all, it wasn't bad.

Headed to Goodwill

I decided to get the bread machine of my dreams for the next batch. I headed to Goodwill and bough their top-of-the-line model for $9.00. The pan has an enclosed bottom, and a larger stirring rod that won't slide off easily. Besides, I could even mount it permanently if I wanted too since it wasn't a loaner.

I didn't like the way that the dough cycle pulsed the stirring arm, so I took it apart and hard-wired the AC motor to a switch. This wasn't necessary, but the geek in me just had to do it. This new setup is absolutely perfect. I can roast a pound of green beans in one 20 minute session and that lasts me two weeks.

The Basic Procedure

I won't go into too much depth, as Sweet Maria's has much better information. I shot a little video just to give a basic illustration (show below), but I also found a nice instructional video from someone else that you may want to watch.

Heating the beans with a hot air source, is a terrific way to get heat into the beans quickly...sometimes too quickly. So I start my beans off with my heat gun on high (1000 degrees), then when they hit about 350 degrees, I slow it down by dropping my heat down to 800 degrees. The beans will begin changing color and then start their first crack. Coffee beans crack just like popcorn, except they do it twice.

Once the first crack finishes, I drop the heat gun down to 700 degrees. The transition from 1st to second crack can be quick, and so you don't want to overshoot your degree of roast. There are a variety of stopping points, and Sweet Maria's goes into exquisite details. They also give you recommended ranges for each of their bean varieties too. I personally like a "Full City" roast, and so I stop roasting about 10-15 seconds into my second crack.

The second crack is quieter than the first crack, and the individual cracks are more rapid. For this reason, I try to make that I build up to the second crack slowly since my bread machine and heat gun make a lot of noise. Once my beans are done, I turn my heat gun's heater off but leave the blower on. Then I remove the bread machine pan with oven mitts and poor them into my metal colander. I then put the colander on top of running fan and shake them about. The quick cooling is important, because the beans will continue to roast after you remove the heat gun.

Once the beans are cooled, they can be stored in a glass or ceramic jar with a loose lid. The will continue to release CO2 for a few hours, so you don't want to seal them in. You can brew with them in a few hours, but I usually wait overnight. I only grind what I need for each pot of coffee to help preserve the freshness. Green beans can be stored for months, roasted beans can go one to two weeks, but ground coffee has to be used immediately.

Wrap Up

I personally think the bread machine / heat gun is the best method for its speed, volume, evenness of roast, and precise control of roast profile. You really don't need a thermometer, but I am red-green color deficient, and so can't detect color changes really well. You can also go by sound alone for most degrees of roast, but I like having the extra information.

You're going to be amazed at how good freshly roasted coffee is. You may not ever buy a fancy coffee drink again. It's certainly cheaper. Most of the beans that I buy are under $6.00 per pound. Add in the cost of my primo $9.00 bread machine and new dog dish, and I'm still ahead.