Rotisserie/Toaster Oven Coffee Roaster (Pic Heavy)

[Sr Mike]

Rick (Galaga) asked me to start a thread on my DIY coffee roaster. Photos are of a dark roast I did yesterday with Honduran beans.

I have been roasting using a Whirlypop for about 7 years now and did some serious thinking to avoid buying a new roaster or Whirlypop.

For me, 3 main components are needed to roast:
1) Heat
2) Churning
3) Cooling

I was going to buy a new roaster, but each had one main problem; cooling. Of the roasters in my price range they all had complaints about cooling. How much I wanted to roast at a time, type of roaster, and cost was my main driving points that got me thinking about my new setup.

A lot of smoke, the roaster is used in my garage.


I used a counter top rotisserie/toaster oven. I made a basket out of 1/4" wire mesh. That turned out to be a small mistake because the mesh was too spaced out, the beans would simply fall through the spacing. To fix this I cut up and lined the basket with a splatter screen. I think even an 1/8" mesh would be too small for a peaberry bean. Either way this is my first basket and will make another in the future. Inside the basket I made a ridge to help tumble the beans with each turn of the basket. I used 2 springs and made cheap hooks to latch the door shut.

The bar that roatates the basket is 1/4", it fits the wire mesh spacing perfectly and turns the basket without a problem

A look at the ridge to tumble the beans:


The spring latch:


The roast takes A LOT longer, but the beans have been roasted to a beautiful even color every time. On average a 1/2 lbs takes 35-38 minuted depending on the beans and the amount roasted, add another 10 minutes for a whole pound. I may make a larger basket in the future, but in reality I only drink 1/2 lbs a week.

1/2 lbs. Honduran beans ready to be roasted:


For cooling, I use a ShopVac and place my thumb over the hose to help give a stronger blast of air. I put the hose against one end of the basket and it cools the beans extremely quick and blows all the chaff out of the basket. After 30 seconds I can dump the beans into a container and be done. In the picture below you can see the beans are beautifully colored, oily, and no chaff.

The roasted Honduran beans:


The beans will not be ready to brew for about 5 days. Unlike my Whirlypop roasting where the beans are good in 2 days. I did not quite realize this until I roasted up Nicaraguan beans. I have been roasting African and Colombian beans because they are not a favorite of mine and was being used as I learn more about my new roasting setup. After 2 days I was not getting the flavor I love so much with these Nicaraguan beans. On day 5 it was an instant change and I got that pop of flavor I was wanting and expecting 3 days earlier.

I think this is because of the way the beans are cooked, instead of the hot steel of the Whirlypop cooking the beans, it is radiant heat cooking the beans. I don't have any previous experience with drum roasters, this may be common, I don't know.

I also get to step away and not be tied to the roaster while it is going, I use a timer and an alarm and carry it with me if I need to walk away. A longer roast time does not bother me. I do listen for 1st and 2nd crack along with peering into the oven and looking at my roast coloration, which is a tad difficult being that my viewing window in my basket is so small. I have very little mess floating around the oven and it is very easy to clean because there is so little mess. The cleaning consists of removing the bottom tray and wiping it down and cleaning the glass.

Total cost is under $75 new. A used oven and it can be done for about $30.

[Chris.]

Nice setup you have there. One thing though. I've read a lot about this recently and most sources say a three minute cool down is about optimal. Yours might be cooling too quickly. I'll be makng my roasting setup in the next day or so. I plan to use a mesh colander over a fan on low to cool my beans. Can't wait to test my ideas out when my first batch of green arrives Tuesday.

[Sr Mike]

Thanks Chris, that may be a possibility I will look into. I have always tried to cool as quick as possible because I did not want the beans to continue to cook once they reach what I find to be optimal.

[Chris.]

That may be the process for a very dark roast like that. All tutorials I read/watched say to pull the from heat during second crack then cool over 3 minutes. The yankeecoffee guy on YouTube says you should be able to brew a fresh batch within a few hours. I won't be able to report my personal experience for a week but I'm looking forward to it!!

[Sr Mike]

After years of roasting, I never bothered with timing my cooling process and was always pleased with the results which were usually cooked to a nice medium roast. I just waited until the beans were warm to the touch and not scaulding hot when I would put them in a container. In general any roast can be brewed in about 4 hours, that does not mean the roast has settled in their peak flavor, you will learn that the flavors will change over a couple of days.

I gave up listening to "experts" years ago on the roasting process because I had my little Whirleypop down perfectly for me. I am still expirementing with this machine. I have never cared for dark roast with the Whirleypop, the beans always had a burnt flavor, I am hoping this will give me good results. So far I have been impressed with this, I just roast with a few extra days to let the beans settle before I am out of my last roasting run.

The basket doen not retain much heat, my hope is the dark roast will be nice and clean in flavor, slight carmel tones without the burnt notes because the surface of the beans are not scourched. I got this up and running about a month ago, still a lot of little tinkering to learn.

[galaga]

Thanks Mike, nice post. I'll point Ted over this way.

Mike - very nice, professional looking set-up there.
A question for you... There is this Set It & Forget It rotisserie oven sitting unused in our kitchen. Well, after seeing your invention, the wheels started turning in my head! The question is whether roasting coffee in the rotisserie would result in residual aromas and flavors in the rotisserie, should the wife decide to someday use the thing for a roast or something??? What does your experience with yours say?
Thx -
RR

[shilala]

Mike, thanks for taking the time to make up the post.
I love watching "necessity is the mother of invention" in action.

[Chris.]

Originally Posted by badbriar

Mike - very nice, professional looking set-up there.
A question for you... There is this Set It & Forget It rotisserie oven sitting unused in our kitchen. Well, after seeing your invention, the wheels started turning in my head! The question is whether roasting coffee in the rotisserie would result in residual aromas and flavors in the rotisserie, should the wife decide to someday use the thing for a roast or something??? What does your experience with yours say?
Thx -
RR

I would say yes, but it's a pleasing, sweet aroma IMO. I use a drill and heat gun to roast coffee and every time I use either of them outside of roasting, I smell the roasting process. Must be tiny particles of chaff that gets stuck in the grooves or something.

I have contemplated turning an old grill into a rotisserie/coffee roaster, but need the old grill first. lol

[MarkinAZ]

Thanks for the inspirational post Mike. Great job and very creative. I'm sure this project will fine tune over time

[tedrodgerscpa]

Sweet!!!!

[ArgusP2]

Fantastic! Is there anything you can't do?!

[Buena Fortuna]

Nice work Mike!
I've seen other roasters like this where they lined the insides with tin foil to increase the radiant heat/reduce heat loss. Reducing your roast time will help draw out more of the natural flavors of the beans and reduce any baking that occurs during extended roasts.

[AdamJoshua]

Originally Posted by ArgusP2

Fantastic! Is there anything you can't do?!

It doesn't dice.

[357]

I saw a George Foreman rotisserie cooker similar to this setup minus the wire mesh. For a few bucks worth of mesh I could have duplicated this design but I missed out on it. I will be keeping an eye out for another one. Currently I'm using my metal geared Whirley Pop with good results but a "set it and forget it" option would be a nice option.

[Buena Fortuna]

Originally Posted by 357

I saw a George Foreman rotisserie cooker similar to this setup minus the wire mesh. For a few bucks worth of mesh I could have duplicated this design but I missed out on it. I will be keeping an eye out for another one. Currently I'm using my metal geared Whirley Pop with good results but a "set it and forget it" option would be a nice option.

Have you considered adding an electric motor to your Whirley Pop?

[357]

Originally Posted by Buena Fortuna

Have you considered adding an electric motor to your Whirley Pop?

Not really. I'm not sure that would have the desired effect. I think my WhirlyPop roasts too quickly to be left for any period of time, plus I like the manual option, i just want to add a more automated option as well. If I motorized it I would likely lose my manual option. BTW, good to "see" you Sam. We need to get together for a smoke sometime.