DIY coffee roasting [Part zero: list of references]

Coffee roasting; how complicated could that be? Just heat some beans until they turn brown, and you’re good to go. I recently found some local green coffee suppliers and realized I can buy small quantities for a fairly reasonable price. So I decided I would build my own coffee roasting setup. This is my journal.

While I work on Part three (spoiler, things get burned), I thought I would share the list of resources I am collected as I build and learn about roasting. Enjoy!



DIY coffee roasting [Part two: roaster designs]

Coffee roasting; how complicated could that be? Just heat some beans until they turn brown, and you’re good to go. I recently found some local green coffee suppliers and realized I can buy small quantities for a fairly reasonable price. So I decided I would build my own coffee roasting setup. This is my journal.

While it was appealing to build my own roaster, if a company had a low-priced, good looking unit I figured it might not be worth going through all the effort designing something…

Retail roasters

There are many home roasting options, but in general I thought they were either expensive and not good quality, or extremely expensive and of very good quality. Common recommendations are the FreshRoast series, the Behmor 1600, or a Hottop; I’ve listed them below with a few comments:

Screenshot 2019-04-05 at 10.22.08
The FreshRoast series appears to be a glorified popcorn popper, with a roast size of just a few hundred grams. The price on is much higher than you typically see. A used one should run you about $200 CAD
Screenshot 2019-04-05 at 10.21.24
The Behmor 1600 is a drum roaster and comes with fairly good reviews from amateur roasters. It can typically roast close to a pound at a time, but is difficult to achieve reproducible results (reviews state this, I’m not totally sure why). This seems like a good option, except the price listed above is in USD and is a big initial investment.
Screenshot 2019-04-05 at 10.19.02
The Hottop seems to be the holy grail of home roasting equipment. It allows for extremely reproducible results, has a cooling tray, and offers a lot of control etc. Clearly $1-2 k is out of the question, but if home roasting became a very serious thing, I would consider jumping directly to this and skipping the Behmor-level gear.

Essentially what I found was that no commercially available roaster fit my needs and budget. Apparently there is a significant number of people who feel the same way. So many, that there is a subReddit almost exclusively for us.

DIY roasters

The r/roasting page is full of people who, like me, want to roast beans at home but not spend too much money. The most common solutions are “popcorn air popper” (so smart!) and to a lesser extent, bread machine + heat gun (uh-oh…)

The air popper solution is kind of perfect; the device gets to the proper temperature, and the fan agitates the beans, just like a fluid bed roaster. The major problem that people run into though, is controlling the temperature or batch size. As far as control, most air poppers don’t even have a temperature reading let alone temperature control. People on Reddit seem, for the most part, to be satisfied with letting the popper reach whatever temperature it reaches, and listening for the cracks.

I like the idea of the air popper, but the idea of having such little control over the process sounds terrible. Lucky for me, Mark Sanders already put together directions for adding a thermocouple and temperature control to any existing popcorn popper. Using a Raspberry Pi microcomputer and a few external components, he built a device that, based on the temperature reading from the thermocouple, will turn the heater on or off. He also wrote a program (in Python) that lets you record the temperature as a function of time save your roast profiles, and repeat profiles you liked. Effectively, this will turn your popcorn air popper into a FreshRoast SR500. Sign me up!Screenshot 2019-04-08 at 16.30.09

This got me so excited that I went ahead and ordered all the parts I was going to need including green beans, and picked over Value Village for a popper. From what I read, most popcorn poppers will work, though in some cases a popper may have trouble reaching a high enough temperature. Typically the older poppers will work better. I ended up finding a beautifully age-yellowed popper that was conspicuously clean and oil-free for a measly $5.00

This is going to be so much fun…

DIY coffee roasting [Part one: Louis-Camille Maillard]

Coffee roasting; how complicated could that be? Just heat some beans until they turn brown, and you’re good to go. I recently found some local green coffee suppliers and realized I can buy small quantities for a fairly reasonable price. So I decided I would build my own coffee roasting setup. This is my journal.

I understand coffee roasting on a superficial level. Beans come dried and unroasted (“green”). By heating the beans, they undergo some sort of browning reaction that makes them delicious. Along the way, the beans “crack”, a lot like popcorn would. There are two cracks that happen, and passing through the “second crack” results in an oily dark roast.

With a bit of research I learned the browning process is due to a specific chemical process called the Maillard reaction. Louis-Camille Maillard was a French scientist who first characterized the process while attempting to reproduce biological protein synthesis. In essence, this is a heat-initiated reaction between amino acids and sugars and is ubiquitous throughout cooking. The browning on steak? Maillard. Brown crust on bread? Maillard. And most importantly, roasted coffee; Maillard.

Clearly the resulting compounds of the Maillard reaction are not identical in all of the above examples. During the reaction, a cascade of molecules are created which depend on the specific amino acids present. The resulting molecules are what give these foods their distinct flavors and aromas, however, the exact collection of molecules that are created are very hard to predict and control. For this reason, I am going to assume most coffee roasting discussion will be more of an “art” than a “science”.

[Is “art” what happens when the science is too complicated? The art of coffee roasting, the art of winemaking, cooking as an art; there are countless examples. Is this admitting that heuristic approaches are required because a process is too hard to fully control? By simplifying details, making approximations, and losing exactness, are we admitting science has failed to describe the process? No. What science has allowed us to do is make informed decisions about how and what to simplify to create a working description that matches the tools we have to enact the process.]

From what I have read, coffee gets tasty between 150-230 C (300-450 F). Along the way there are chemical events that happen at specific temperatures. For right now, those details are unimportant. What is important is that the roaster can reach temperatures up to 230 C (450 F), and will provide even heating to all of the beans. Most commercial solutions seem to involve either a rotating drum which agitates the beans as they heat, or blowing hot air such that the air agitates the beans.

I wonder if I can do better…

Further reading and sources:

[1] The first place you should go (Wiki)

[2] Coffee and the Maillard reaction

[3] Coffee roasting and equipment


New Orleans #2


It’s been a few days since we arrived in New Orleans. We’ve managed to visit a few really good coffee shops, take down a couple really good cocktails, and only found ourselves on the wrong side of one (1) hangover.


What really stands out to me is the contrast between their classic, indulgent architecture which has lasted for hundreds of years, and the hanging-on-by-a-thread damage that a lot of buildings have sustained. It sort of feels like I’m witnessing the last days of something great, though I know the people won’t let that happen.

I’ve also noticed, and this makes a lot of sense, that cold brew is very big here. Our first specialty coffee stop was Spitfire Coffee in the French Quarter. This is the big Mardi Gras, tourist-y neighborhood, so I would imagine rent is very high. Spitfire makes due with a small closet which seats four at the most. Not a problem, since you really want to be walking around this area. I don’t recall anything about their beans, but I do remember it being subtley sweet and very chocolately, something hard to accomplish with anything but a true cold-brew process. The barista working had a lot of good suggestions when it came to specialty coffee, and was legitimately excited to tell us about his favorite spots.

For the rest of the afternoon, we slowly made our way across town into the Garden District. We stopped in a few bars and a few parks along the way. Most notably, a writer-themed bar called Backspace and Louis Armstrong park,


The Garden District, as you may imagine, was lovely. It is on the other side of town from the French Quarter, and as such, much cleaner, and much more relaxed. Now by cleaner, what I mean is that there is less trash strewn about and the houses appear newer and in better condition. That doesn’t mean it lacks things like residential chickens, because it most certainly has those.

Our coffee stops in the Garden District included Cherry Coffee Roasters, and Mojo coffeehouse. Both pulled really nice espresso blends, and offered many single-origin beans to take home. Mojo was pretty busy when we went, but the barista serving us was quite pleasant and… possibly Australian. We spent more time at Cherry, taking a bit of a break from all of the walking. It was much less busy here, and we had the opportunity to chat with the only barista working that afternoon. She suggested we check out the Bywater and 9th Ward neighborhoods for their waterfront parks and generally artsy-ness.

We spent the whole day out, and saw a lot of street performers along the way. Two highlights; a band called Holy Locust (they are on Spotify) and this group of brass players on Frenchmen street.


FYI, the first beans being sent out for the March coffee club have been picked, and they are from Mojo. I am really looking forward to sharing these with y’all. If you’d like to try some, join the club over on Patreon.





New Orleans #1

Andrea and I left Hamilton at 5:00 pm on Friday after grabbing some American dollars and road beans from Durand. We decided not to obsess about the time we left since we would be driving through the night no matter what.

I’ve been fantasizing about a long, non-stop drive since discovering Dream Whip, at the recommendation of Dave at King West books. The idea of crossing the country, and having as much time and space as you’d like sounded ideal.

Part of this fantasy included having a nice coffee early in the morning among strange, foreign scenery, far away from anything familiar. I’m currently writing a guide to making coffee outside and figured this would be an ideal time to test some things. I packed my kettle, camp stove, and French press and planned on stopping somewhere off the highway to watch the sun rise.

Our first coffee stop was in Ohio. We were just getting the kettle filled with the water we brought when I realized I had forgot gas for the stove.

Plan B was to ask for hot water at rest stops and gas stations. Part of the article was going to focus on where and how to get the resources you are missing. It turns out getting hot water is exceedingly easy. Provided you are satisfied brewing at a rest stop rather than the edge of a cliff, all you really need is a cup, your brewing device, beans and a hand grinder. Typically you can get hot water for free anywhere coffee is sold.

Only one person charged us for water. We met a strange, drawling charecateur of a man at 3:00 am in Kentucky, off a forgotten exist, far from the highway. His station was next to a boarded up Motel that oddly still had “Open” sign. After paying, he kept us at the register for a while as he relived the story of a murder-suicide he witnessed two nights ago right at this spot.

Getting back to the highway, we were diverted to a winding, single lane dirt road that seemed to go on forever. There were no lights except from the occasional, distant farmhouse. Part way along, we came across a small group of deer making their way to the other side of the road. We would meet nearly a dozen before we made it back to the I-65 South.

We took our one and only simultaneous break at the edge of Kentucky and Tennessee at 6:00 am. We parked in the back of a truck stop, locked the doors and had an hour nap. Andrea’s car is a late-era Grand Marquis, so the back seat was essentially a double-bed. Waking up with the sun that day was one of the most beautiful things I’ve experienced.

We got moving again by 7:00 am, and after a few more coffee stops, we arrived at our AirBnB at 7:00 pm local time, right as one of the many pre-Mardi Gras parades was ending.

Welcome to the club

Hi! I’m Adam, the guy behind A+S. I’m a physics graduate student and coffee lover.

coffee man science glamour model beauty so pure so sexyAs a grad student, I have a professional relationship with coffee. Like many jobs that require long hours and concentration, grad students – even if they were never coffee drinkers before – will eventually find their way to the stuff. “Come on, just try it,” they said. “We need to get all this work done by tomorrow, I think Starbucks is open late,” they said.

I’ve personally never really felt the performance-enhancing effects of caffeine (though I have felt a caffeine OD, a story for another time). Still, my coffee habit really developed in grad school. I found something comforting in having a warm drink while I work. Later I discovered that brewing my own coffee gave me a moment to take a step back, clear my mind, and re-focus. And of course it was fun discovering interesting (and sometimes uniquely horrible) roasts.

I’m not a barista (though I have taken part in the Canadian Aeropress Championships). I don’t have access to all the latest tools, nor the time to perfect the art and science of coffee (I’m currently trying to learn the art and science of science, after all). However, I do appreciate a good cup, enjoy exploring flavors, and have a DIY mentality I bring to pretty much everything I do. I find digging in a figuring out how all this stuff works to be fun and rewarding, but that doesn’t mean you have to. And that’s the reason for this blog. I want help you brew the best coffee with whatever time and tools you have access to, according to your tastes and interest level. There’s no wrong way to take your coffee, and there’s no reason you can’t brew something you love.

If this all sounds good, then welcome to the club! In the following weeks I will be writing and sharing a few basic brew guides (The Office Coffee Guide is already up). I will also be reviewing coffee and gear. If you already have a coffee routine, great! You may be interested in the new cafes and beans I try (I am based in Hamilton Ontario, near Toronto). In the coming weeks I will be visiting New Orleans and Boston, drinking and writing about as much coffee as possible.

Finally, if you’d like to try some of the unique beans from my travels and want to support the site, consider joining the Patreon. Patrons will receive three (or more!) different and exciting coffees every month from great roasters around the world- ground, packaged, and vacuum sealed to your specifications.

So there yah go. That’s who I am and what this is all about. Thanks for for reading, and I look forward to (figuratively) diving into all this coffee with you!