I have been a coffee drinker half my life. It started in Amsterdam while there on a mission trip during college. Dutch coffee was unlike anything I had ever tasted. Back home, I limped along with store bought brands, which at the time were pretty terrible in the mid 90’s. Eventually the Coffee Company That Shall Not Be Named (C.C.T.S.N.B.N.) entered the picture and, well, it was the best thing going. You see, Florida is not known as a “coffee culture” and 15 years ago it was still pretty much a wasteland of bad coffee. But as I began to make friends around the country and see the wonders to behold that could literally be bought for reasonable prices in a legit coffee shop down the street, it made my daily appointment with a bag of C.C.T.S.N.B.N. coffee that much more depressing.
In 2008, my dear mother-in-law changed everything. Perhaps she was tired of my daily coffee rants at the office (we have a family engineering firm). Or maybe she just felt like I needed a hobby. Regardless, that Christmas she gave me a Freshroast Plus air roaster and a pound of green coffee. I had no idea what I was doing, and those first few roasts were probably terrible, but boy was that coffee fresh. And with that, I was hooked.
After a year of trial and error and hours spent on the back porch, I began researching other methods of home roasting. The Freshroast only yields about 3 oz of coffee and that just couldn’t support my habit. I won’t bore you with details, but let’s just say the next two years were spent searching Goodwill and eBay looking for popcorn poppers of all varieties. Basically, once I figured out you could mimic the same performance of a Freshroast roaster with a slightly modified (and slightly unsafe) popper, my cadre of roasters grew to four. I could now roast up to a pound of coffee at a time, although it took about an hour, was incredibly unpredictable and messy, and statistically I would likely burn the house down within 12-18 months.
So in 2011 I began the process of building a BBQ grill rotisserie roaster. Outside of an honest to goodness commercial grade sample roaster, the rotisserie method is the least expensive and closest representation of authentic drum roasting you can get at home. It is a bit crude, but after all, people have been roasting coffee over an open fire in a skillet for generations. At the end of this post I’ve compiled a basic parts list. There are options for a bit more money that will come pre-assembled, but to me half the fun was putting the thing together.
So, how do I roast coffee in this contraption? Well, after about 20 batches with very mixed results, I finally settled in on a process that gives me a consistent roast every time. It starts with excellent green coffee. For a home roaster, there really is no better place to buy than Sweet Maria’s. They have a continuously revolving storehouse of excellent, small batch coffees that were purchased at a fair price from farmers and co-ops around the world. This coffee is better than Fair-Trade…there is real relationship behind the scenes ensuring that the farmers get their due. I typically order 20 pounds at a time at between $5-$6.50 a pound and shipping is a very reasonable $8.99 for UPS Ground. Do the math the next time you go to C.C.T.S.N.B.N. and pay $15 / lb.
To start a batch, I load 2 1/2 pounds of green coffee into my drum and pre-heat the grill to approximately 450F. The three most difficult things about home roasting are temperature, temperature, and temperature. Basically, a grill thermometer is complete crap, but with some trial and error I settled on final roast temperature of approximately 440F – at least at the top of my grill. What this corresponds to in the drum is anyone’s guess, but it works. Once the drum is loaded into the grill, I flip the switch and the rotisserie starts turning (at ~50 RPM which requires a special gear motor – see parts list below).
For the first few minutes, the grill must heat the drum and coffee back up so the grill temperature levels back out at 440F. Again, much trial and error. After about 10 minutes, I hear the beginning of the “first crack”. The biggest weakness of a home roaster like mine is the inability to see where the roast is at during the process. So I have learned to completely rely on audio cues and “feel” to hit various roasting levels. This handy guide from Sweet Maria’s shows you what all the levels look like. Most of the coffee you get from C.C.T.S.N.B.N. is roasted to Full City + or even Vienna. This is why their coffee has that signature “charred” taste. Literally, the coffee is roasted until it begins to turn into charcoal. With great coffees, darker roasts can enhance richer flavors and make a very consistent product. But it can also mask the flavor of inferior beans and make everything uniform. Hence, an easy way to make average coffee taste a bit above average once you’ve snookered the average consumer.
The first crack sounds much like popcorn popping. After the first crack begins to fade, I open the cover and pull the temperature back to about 375F. This slows the roast down, otherwise it will run like crazy into carbon-land. After a few minutes at lower temperature, I’ll crank the heat back up and take it to the verge of the “second crack” which sounds like Rice Crispy’s in a bowl of milk. Generally I like to roast to Full City or just barely into the “second crack”. I’m partial to Central and South American coffees and Full City suits them well.
The finished product gets dumped into my make-shift cooling rack (basically a box fan blowing upwards in a home-made wooden rack with screen on top). After a few minutes of cooling it is done and is ready for grinding by the next morning (although at its peak of flavor in about three days). A roast of 2 1/2 pounds of green coffee yields approximately 2.2 lbs of roasted coffee (evaporation my friend). This lasts me two weeks or so, which is right about the time the coffee starts to get stale!
Imagine every day having a cup of fresh, flavorful coffee that you roasted yourself for less than half of what it typically costs! Here’s what you’ll need:
1. A cheap gas grill, 30,000 BTU or greater. This should be obvious, but don’t use the grill you cook burgers on, unless you want your coffee tasting like grease!
2. A drum. There are at least two sources – RK Drums which are very well constructed (and expensive). Or, you can get one on eBay from this guy! I recommend the 5 lb model.
3. A rotisserie kit. Throw away the motor. You won’t need it, because you will be buying a….
4. A gear motor and coupling. I’ve linked to the kit at RK Drums because it shows what you’ll need. But again, you can look elsewhere and find the same stuff cheaper. The coupling is very difficult to find though. Actually, if anyone can find one please let me know!
5. A box fan. You build the frame and mount the fan on top with a screen tray. Note that the fan has to blow upwards. Oh yeah, I forgot to mention that coffee roasting results in a lot of chaff flying everywhere!
6. Welding gloves. Stuff gets hot, man!
7. Digital kitchen scale. Gotta weigh out that green coffee and the finished product to share with your friends!
All this will cost you between $400-500 if you choose the eBay drum. If you go RK, you’ll spend about $200-300 more. If you spend $14/lb on coffee now (which is on the low side), you will be saving approximately $7/lb. If you’re like me and drink a pound a week, that’s a savings of $364 a year. Your roaster will pay back in a little over a year. Thank the Bishop later…and let me know if you want to sample mine anytime!