I've been a home roaster for the last 8 years. Along the way I've studied a lot and developed practices and methods . . . some I don't even remember why I do it! Right now I roast EVERY kind of coffee the same way. I'm looking for ways to improve my general practice, but more than anything I really want to learn how to approach individual coffees, because right now I really have no idea how varietal, density, elevation, origin, etc. differ in the way they take roasts, so I roast them all the same way. I would appreciate any feedback, suggestions, advice or resources.

I currently use a Quest M3, with a painted drum. I mainly roast Ethiopians and Kenyans, but have recently started roasting PNG's, Brazil's, Guat's, Costa Ricans, etc. Here is my stand by practice:

115g Charged at 325F. The Heat is at Zero for the first 30 seconds and then from 30-60 seconds a slow ramp up to max heat (12). When the beans turn (Typically around 190F), I drop the heat to 10. At 300F I close the bean chute hatch (I leave it open to prevent any airflow during drying phase) and put the airflow at 5-6 and drop the heat to around 8.5. Around 355F I apply full airflow (10) and possibly drop the heat to 7.5-8 if the ROR is still over 35F/min. First crack occurs around 385F and I aim to get the ROR below 20F/min, preferably around 10F/min by reducing heat further if necessary. I always reduce heat during the roast, never add, a la Scott Rao's method. I carry the roast about 10 seconds past the end of first crack and drop. Total roast time tends to be 8-9 minutes, with FC-Drop being about 18-19% of the total roast time.

So there it is, I do that for every roast. I get good coffee, but I'm looking to perfect! Any advice or feedback is greatly appreciated!

Naturals vs Wet process you charge lower and roast a bit slower with naturals..
Also low grown coffees lower and slower like naturals vs high grown hotter charge and faster are like wet processes..

Asian (PNG) coffees roast a little darker..

I'm pretty much in the same boat as you..
I don't take the time I should to think through my roasts before I head out to the garage..
I stay stuck in same ol' same ol' method and need to break out!

Favorite current book to tune my roasts is Modulating the Flavor Profile of Coffee by Rob Hoos. There's a summary and table at about page 59 for what happens when you go shorter or longer at different stages. There's also the excellent and growing list of videos at Mill City Roasters.

You can get a coffee that others are roasting and try similar profiles, comparing tastes. Take one coffee you already like and make one change in the profile. How is it different? Look for current profiles using your roaster because it's different on different machines.

1+

Buy 10-20lbs of a single origin

Roast one with short development other with long. Play with this for all of the phases. Cup them side by side


I have an El Salvador right now that for some reason is a little tart on my quest with my standard development/drop temp. I've been taking it about 5 degrees hotter and a slight extension of development and I get a nice round orange and toffee, before it was kinda like tart cherry and hibiscus. This took me about 6 batches to find where I liked this coffee.

I charge higher for denser Colombians and Kenyas and will develop them a little more, but I sort of have my standard profile and deviate on my second batch to see what will change

thepilgrimsdream wrote:
Buy 10-20lbs of a single origin

This was the single largest change I made which helped me improve.

When I started years ago, I bought every coffee under the stars and really never got my roast down before I ran out, then off to another.

COFFEE JUMPING.....

Now I buy a minimum of 10# of one origin at a time.

I start the roast of the new green using my "old standard" of heat and damper (wet and natural process uses a different "standard").

I start "pumping the tryer" around 390 degrees and try to pull a glass of beans (20 gr +/-) every 5 degrees going only to 435 degrees (10 samples) then dropping the roast.

I will then cup each temp pull and decide where that bean wants me to roast it.

Once I determine where to go, I do a single roast at that profile and if it is still "on" I will print that profile and follow it for every subsequent roast.

This works for me but as with anything that involves personal taste YMMV

The above, and then modify that profile at other stages too per Rob Hoos's guidelines.

turtle wrote: I start "pumping the tryer" around 390 degrees and try to pull a glass of beans (20 gr +/-) every 5 degrees going only to 435 degrees (10 samples) then dropping the roast.

I will then cup each temp pull and decide where that bean wants me to roast it.

This ...is...so....smart.... what a newbie I am for never thinking of that, and also why I need a roaster with a trier!

dale_cooper wrote:This ...is...so....smart.... what a newbie I am for never thinking of that, and also why I need a roaster with a trier!

+1 on that trier!
My homemade roaster has no trier, so I'm left guessing by nose. A nose that I've neither developed for roasting, nor corresponds to anything on that bean in particular.
Someday I'll likely end up with such a roaster the way I'm going.

Thank you everyone for the great advice!

JK wrote:Naturals vs Wet process you charge lower and roast a bit slower with naturals..
Also low grown coffees lower and slower like naturals vs high grown hotter charge and faster are like wet processes..

Thank you for sharing this! Can you (or anyone) tell me why you charge lower and roast slower with naturals and low grown coffee?

Roasty wrote:Thank you everyone for the great advice!



Thank you for sharing this! Can you (or anyone) tell me why you charge lower and roast slower with naturals and low grown coffee?

I think they are more easily burnt or scorched.