Over the last 20 years or so I have used a wide range of equipment, from air popcorn poppers to $thousand+ programmable machines. After all that this is what I ended up with, a 1-pound roaster that lets me dial in perfection:
Bottom is cast iron dutch oven, top is a modified cast iron skillet. It is 13 pounds of thermal mass against a 1 pound of coffee beans. The egg-beater looking thing is from a Kitchenaid mixer, modified so as it is spun by hand around the hole on the lid, the shape follows the contour of the base while the opposite side reaches the center of the container. The hole on the lid is dialed in so it fits through it. The way I use it is by preheating it to 400 degrees (takes a while to warm up all the way to the lid) which lets me hit first crack around 4.5 minutes without charring the beans. The holes on the bottom where the final dial-in step to allow of better temperature control. It largely relies on the ungodly amount of thermal mass but it had a delay in raising the working temperature inside of the chamber; raising the flame had about a 20~30-second delay before the beans would really feel it. This was the best way to have my cake and eat it too; the thermal mass plus more direct raising of the temp.
Roasting the most perfect cup of coffee requires very precise attention to details throughout the roasting process:
Ramping up to first crack. The beans go from green to just beginning to develop color. They are full of humidity so there is a limit of how much heat you can apply because they just keep “sweating it off”. But if you put too much heat you end up charring the outside, if you don’t put enough heat you end up “baking” the beans instead of roasting them. The best metric for success is hitting first crack at around 4 1/2 minutes of roasting with an even roast across your beans. There are specific acrid notes you can detect in your coffee from screwing this step. This is the hill stovetop methods come to die on, while air roasters have an easy time pumping the correct amount of heat.
First crack. Beans are losing humidity and beginning to pick up heat. You want this step to last at least 2 minutes. If you rush through it you’ll lose a lot of body in the cup, ending up with a thin profile and no mouth feel. You see a lot of “smoke” coming out but at this stage it is mostly vapor. Towards the end you have to start cutting back on temperature as the much lower humidity allows the beans to really soak up heat, which can lead to them getting ahead of you.
Between first and second crack. This is a crucial point to realize the full potential of the cup. What you see at this stage is the actual smoke from the roast and the nose can tell. Oils are beginning to migrate, and you do not want to rush that. This is also the step you can tweak the most in order to get the best expression based on the bean variety you are working on. As a matter of fact I ended up settling on a stovetop roaster because of how it lets me be 100% hands on. You want to make sure you spend a good amount of time at this juncture, you want to make sure you are still gaining heat and not baking your beans, and with the stovetop I can monitor all that by the amount of smoke it generates. I don’t want the smoke to stop (baking mode) nor I want too much smoke (burning mode) I can hit that note where a wispy amount of smoke is being generated which tells me that my beans are just soaking up enough heat to keep that going. You really want to spend at least 5 minutes in-between cracks, but this is really where things turn into an art form. At the end the proof is in the cup.
Second crack. It gets complicated to consistently hit light roast pre-second crack, as you have to rely on temperature measurements. But I usually don’t roast those so for me life starts at second crack. At this stage your beans are so dry that you can simmer through the previous step, and at the end just raise the temperature and hit second crack in a hurry (the holes on my design I talked about, this is where I found out they helped). The beans are so ready to soak up the heat that I can remove the lid and finish my roast in the open.
There you have it; many hours wasted chasing the perfect roast. At the end not even the $1,400 Hottop was able to cut it, but this one did.
Interesting design you came up with. All makes good sense, except the holes in the bottom. Are you using this on an electric burner; seems there might be issues with the holes on a gas flame.
I am also curious how you got such a perfect hole in the lid.
Actually it was with a gas burner in mind. It allows for some of the hotter air to flow in but is not like the flames could. It slightly improved my ability to inject more heat on the beans. Not a super critical design feature but it helps. The overwhelming bulk of the heat comes from the thermal mass of the cast iron.
I’m going to be honest, I don’t even remember how I did that hole. Nowadays I have a plasma cutter but my coffee roaster precedes me getting that tool. Chances are I used the drill press to drill the perimeter of the hole, maybe a skillsaw to finish the cut (you don’t want the holes touching or the bit can get jumpy, not a good thing on a high torque drill press) and then grinding and a spindle oscillating sander to clean it up.
Interesting. I have quite a few cast iron pots like that and could “spare” one for a roaster. Just curious, how important is the cast iron lid? Would be much easier for me to “transplant” the lid from my stovetop popcorn popper, if that would work.
It depends on how anal you want to be… Just a cast iron pot would give you a good amount of thermal mass that can release a very controlled amount of heat. The lid enhances that; instead of heat flowing straight out of the pot, the lid thermal mass is heated and it reflect said heat back. Imagine heat as a balancing act; without the lid you struggle more to keep that perfect balance but with it makes it easier to maintain an even temperature throughout the process.
Short answer no, you don’t need the lid But with a caveat; having the better temperature control the lid provides allows me to roast a slightly larger batch. Your roaster will have a capacity, dictated by how much you can roast without ending up unevenly charring beans. With 1 pound I can watch my beans gaining color very evenly. If I put 1 1/2 pounds and still try to make it to first crack in around 4 1/2 minutes, the batch doesn’t roast evenly.
I found out when i grind the beans they can be giving off co2 more rapidly at first as you mentioned. They can easily inflate a bag. They can blow coffee all over me when i remove the lid of my bullet blender, if i grind them when they are still hot. The coffee is wonderful and i wanted to thank you again for the advise.
Camellia sinensis (the plant tea comes from) is hardy to zone 7, though I suspect it’ll struggle in the colder parts of zone 7. Youpon and Dahoon hollies are also zone 7, but they seem to be marginally hardy to zone 6. There’s a South American holly with caffeine as well, but it’s less hardy than tea camellia.
So there’s probably a thin zone somewhere around 6b/7a where you can grow caffeine-bearing hollies but not the camellia used for tea, then in warmer zone 7 you can growth both, and in even warmer zones you can grow the South American species (I think it’s upper zone 8 for yerba matte, but I could be wrong).
Neither American species of caffeine-bearing holly has as much caffeine and theobromine (a similar stimulant that’s also found in chocolate) as tea camellia, but they do have some. Theobromine and related chemicals are not as strong neuro-stimulants as caffeine, but they can act as muscle stimulants and can even cause arrhythmia and other issues. It’s actually theobromine which makes chocolate poisonous to dogs. Coffee itself does not contain theobromine so consuming as much caffeine from camellia tea or holly tea as you normally would from coffee might have different or more pronounced side effects (might, though, because caffeine itself gets converted into theobromine in the body). Which is all to say that it’s not dangerous to drink lots of tea or holly tea, but it might give you the jitters a bit more than regular coffee does for the same dose of caffeine.
Yeah I think east coast zone 6b/7a is going to be much more doable than west coast 6b/7a for something like this, especially given that it’s an evergreen.
If you frequent the home-barista.com or Reddit forums - the hardcore folks will say to never use a commercial grinder for home.
Why? Typically you make 2-5 espressos at home vs 100s at a commercial place. There is coffee retention in commercial grinders- almost 2-5 g. It is not an issue when your volume is so high but becomes an issue at home. This is stale coffee that is going into your next cup.
Also you never want to load beans in a hopper for too long - beans go stale.
The newest home grinders have very low retention- 0.1g or less. And single dose. No hopper.
And allow you to taste every nuance in the cup.
That said- the good home grinders cost as much as commercial. Often much more.
The issue with at home grinders is that they’re not very good in my opinion and experience using both.
You don’t have to fill the hopper all the way and there are machines now that don’t hold too much. You only want to grind what you use. Also 9/10 people the business have no idea what they’re doing and it’s the blind leading the blind. I was taught wrong for my first 4 years and it took a few professionals that i met that taught me how wrong i was despite the years and despite being taught by someone who had been doing it for 15 years.
Also it’s good habit to use the first grind to prep the machine. The first shots in the morning seems to help warm everything up in the machine. I always discard the first pull and start a second one for whoever came by first. The grinder also needs adjustments almost every morning depending on the weather and barometer pressure so it may even take a few grinds and adjustments to get it right in the morning. But not everyone is as picky as me on coffee these days also shots hitting ice first thing before warm anything will cause a chemical change as well I’ve been told yet no one else here seem to have been told that.
I would still suggest a commercial one vs one sold for personal use. I like Nuova Simonelli machines but I’m biased with them so…
This one is better than the nuova simonelli single group Appia. I had a Nuova Simonelli Appia 2 but sold it after less than half a year to FilCuisine in Kent. I used it for a few events and at home and did not like it. The bigger commercial ones are built better. I love the Aurelia lines and I’ve had 2 of them. One for home use and one for business but they’re heavy as hell so i got rid of the home use too since i broke up with my ex and couldn’t move it myself. My husband isn’t as addicted as my ex so no need for another high volume machine personally but i absolutely love the Aurelia
But with a caveat; having the better temperature control the lid provides allows me to roast a slightly larger batch. Your roaster will have a capacity, dictated by how much you can roast without ending up unevenly charring beans. With 1 pound I can watch my beans gaining color very evenly. If I put 1 1/2 pounds and still try to make it to first crack in around 4 1/2 minutes, the batch doesn’t roast evenly.
also shots hitting ice first thing before warm anything will cause a chemical change as well I’ve been told yet no one else here seem to have been told that.
