Heat gun coffee roasting

[Chris Hennes]

At this year's eG Candy & Confection Conference eG member tikidoc pointed out that there is another use for heat guns besides melting chocolate: roasting coffee. Has anyone else around here tried this? What have your experiences been?

[MikeHartnett]

I do it weekly. It may not bring the perfect results of professional equipment, but it's incredibly convenient, it works very well, and it brings a level of customization to the coffee experience you can't otherwise get. Personally, I prefer coffees with a lot of brightness, so I go on Sweet Maria's, choose brighter coffees, and tend to roast them in the city to city + range. That way, I get what I want out of coffees, and if I don't, it's my own fault.

[scubadoo97]

This method caught on about 8+ yrs ago. I adopted the technique after becoming frustrated with my Fresh Roast roaster due to the uneven super fast roasts and the small batch size. At the time it was called the heat gun dog bowl method.

Does it work? Absolutely. Will you get tired holding a heat gun and stirring beans for 10-15 min? Absolutely.

I attached my heat gun to a mic stand so I didn't have to hold it but still tired of stirring non stop for 15 min. Do a search on the web and you will find some creative alternate methods using a heat gun. One which I have not tried but appears it would work well is a mounted heat gun over a bread machine. The bread machine is used only to hold and stir the beans while the heat gun delivers the heat.

[tikidoc]

I know you and I already talked about this, Chris, but for everyone else, I think this method works really well. I have previously owned a couple of different drum roasters purchased from Sweet Marias (a fantastic source for green beans, BTW) but they only lasted about 1-2 years, and I got tired of shelling out the money. I tried the WhirlyPop method but ended up with inconsistent results. I got a popcorn air popper (the one everyone recommends for coffee) but the batch sizes were tiny, and I kept having the beans fly out.

Enter the heat gun method, linked above. I roast coffee on my front porch in a stainless bowl nested in a larger bowl, which keeps the outside relatively cool. It takes me about 10-15 minutes to do 8-12 ounces. The result is a very even roast, assuming I don't get distracted by my kids and stop stirring. I really like the fact that I can hear the first and second crack very well, and that I can watch the color change as it roasts. With the drum roasters, the machine was so loud I barely heard the cracks, and I could not monitor color, because the windows get cloudy quickly (if they have a window). And if the heat gun dies, I go to Home Depot and get a new one for about $30.

As far as getting tired of stirring, I honestly don't mind. I sit down on the porch, put on noise canceling headphones, and listen to some music.

Jess

Edited March 23, 2012 by tikidoc (log)

[scubadoo97]

Chris, another interesting method which I've been using for over 6 yrs now is the stir crazy/turbo oven roaster. The stir crazy does the stirring and the turbo oven provides the heat.

[MikeHartnett]

As far as getting tired of stirring, I honestly don't mind.

Same here. Really not a big deal.

[mkayahara]

I've used this technique a couple of times, and will likely do it again soon. A friend of mine introduced me to it, and he's rigged a wooden spoon up to a power drill to do the stirring. (I've never seen it in action, though.)

[rotuts]

I personally use an iRoast II, and by cooling the machjine twice (which seems critical) its lasted 9 years with weekly roasts. A friend of mine does the heat gun and there are a lot of vids on YouTube including the breadmachine method as mentioned above:

http://www.youtube.com/results?search_query=heat+gun+coffee&oq=heat+gun+coffee&aq=f&aqi=&aql=&gs_l=youtube.3...1567l5020l0l5569l15l11l0l0l0l0l0l0ll0l0.

Home roast if you can do it is especially superior and the green beens from Sweet Maria cant be beat. Over time you will find both your personal blend and roasting temp that cant be purchased anywhere.

Edited March 24, 2012 by rotuts (log)

[Chris Hennes]

On Friday I tried this for the first time: the beans were the Ethiopia Limu Jimma - Alaga Sekala from Sweet Maria's, which I chose to do first because SM's suggests a lighter City to City+ roast, and I thought it best to do a light roast as my first. I did the roast on my back patio, but my strategy here backfired as my lawn guys showed up about five minutes into the roast, so I couldn't hear a thing! So I roasted purely by appearance... here is what I wound up with:

It's probably a bit under-roasted: nevertheless, I tried my first cup this afternoon and it was very good. The coffee itself is quite light-bodied with some interesting fruit tones to it. I'm looking forward to playing around with this, especially while the weather is good and I have an excuse to zone out on my patio for 20 minutes.

[rotuts]

you will never fail with beans from SM.

what you do with them after that is up to you.

enjoy the finest Greens you can get.

study your personal results and keep a log.

eventually you will have the 'Personal Perfect Cup'

which is the goal.

Edited April 1, 2012 by rotuts (log)

[tikidoc]

Nice job, Chris! What other beans did you get? I think my favorite in recent memory from Sweet Marias was a Panamanian coffee from Boquete. If you have never tried a Panamanian coffee, I would recommend you do so the next time you order. I'm probably a little biased because I lived there for a while and really love the country, but I think a good Panamanian coffee will rival the best from anywhere else in the world.

I have found that color gets me into the ball park, then once I know I am close, the headphones come off and I use a combination of sound and color to decide where to stop the roast. Don't forget that you will get a little carry over, so stop just a smidge lighter than you want.

[rotuts]

It really does not matter how you get to your own personal 'roast'

what matters is:

1) you get top quality green beans. SM does this finely for you.

2) you get a personal consistent end point (that you can reproduce) for the method you chose to use for that roast so you can use that as a reference point in the future. Color? Crack? Temp? makes no difference.

3) then you blend for your self and keep notes on what you have learned.

eventually you will find a 'personal profile' that cant be purchased anywhere.

Enjoy!

[MikeHartnett]

Let us know what you think after tasting it!

[Chris Hennes]

Nice job, Chris! What other beans did you get?

I ordered the 4lb sampler box, which in this shipment came with the Ethiopia Limu Jimma from Alaga Sekala, the Brazil Fazenda Santa Mariana, the India Poabs Organic Seethargundo Estate, and the El Salvador Majahual from Tablon La Montana.

[MikeHartnett]

Sorry... Just re-read your post and saw you did taste it. But let us know what it's like tomorrow. Usually, you need a good rest period before it reaches its peak.

[Chris Hennes]

I had read 24-48 hours, so I gave it about 45 before my first cup.

[mkayahara]

Have any of you been able to get any really dark roasts using this method? In the four times I've tried it now, I feel like I'm barely getting past first crack. I realize I'll need to do it a few more times before I feel like I've got good control over the process, but so far it seems like it gets to a certain point and then just stops, regardless of how long I point the heat gun at it. Any thoughts?

[tikidoc]

I have definitely gotten into second crack, with good results. I usually stop just a little into second crack, although I have gone a bit further than I wanted once or twice and started to have the beans start to look a little oily. The time between first and second crack seems to vary quite a bit depending upon the bean I'm using. I have not timed it but there is definitely a difference from batch to batch and bean to bean. I would say to be patient and keep stirring.

Have you used other methods before, so that you know what you are listening for? For those who have not done much coffee roasting, first crack is more like a popcorn sound, but a little quieter. Second crack is kind of like an amplified Rice Crispies in milk sound (similar sound but louder, but not as loud as first crack).

[mkayahara]

This is a good point, tikidoc: I haven't tried other methods, so I'm not completely sure what I'm listening for. I'm actually pretty sure that my first couple of tries didn't even hit first crack, because there was no audible cues at all. On the other hand, it can be hard to hear much of anything over the fan on the heat gun and the beans being stirred. I'll keep at it and see what I can get. I've only got a pound left of my current green beans, so maybe I'll try something different next time. There's nothing quite as fun as changing multiple variables at once!

[tikidoc]

Check out http://www.sweetmarias.com/library/content/using-sight-determine-degree-roast, for an idea of visual cues. Sweet Marias' website is not just a great place to buy coffee and equipment, it has a huge wealth of information about beans, roasting and brewing.

I'll look around and see if I can find a video that has first and second crack so you can hear the difference, but think popcorn for firat and Rice Crispies for second. You should be able to hear it even with the heat gun. I usually have my fan on high. One of the reasons I like the heat gun method is that I can still hear the cracks well, as opposed to more contained methods like drum roasters, and obviously you can see everything going on too.

Jess

Edited April 9, 2012 by tikidoc (log)

[Paul Kierstead]

I can very clearly hear 1st and 2nd crack with my Behmor drum roaster, and I could even hear it over the roar of my iRoast 2, though it required some careful listening for the 2nd crack. I like your popcorn and rice crispies analogy, that seems about right.

[mkayahara]

Thanks for your help, tikidoc. I just did another roast today; the first crack was very distinctive, and I think I may have even taken it a little way into the second crack. I'm trying to figure out what the variable is here, since I've been using the same batch of beans from Green Beanery. My current suspicion is that it has to do with wind: both times I've heard a good solid first crack, the air has been still, while last week's roast took place in slightly windier conditions.

In any case, we'll see how this one turns out, flavour-wise. I'm down to my last half-pound of green beans, so I'll have to buy more soon, I guess! Then start figuring out the parameters for an espresso blend...

[rotuts]

I don't wish to take any business away from Green Beanery, I really don't.

one of the very nice features of Sweet Maria is that they have 'sample packs'

at a good price. to introduce new home roasters to various beans. Well worth getting those.

and no, its not stuff they would other wise not be able to sell. I dont work for them etc.

but ive been there several times in the past to pick up.

you can mention the method you brew for the bean selection: drip, espresso etc.

try their sample packs. it gets you on your way for your own 'personal blend'

http://www.sweetmarias.com/sweetmarias/coffee/samplers/green-coffee-sampler.html?source=side

get the "8 lb sampler" no worries you will learn a lot from this.

NB: espresso is a little different than 'drip'

happy roasting!

[tikidoc]

Agree with rotuts on the sample packs from SMs. I order from them a couple times a year, and usually get a sample pack as well as several coffees that I pick out. I have received some really good coffees in the packs, some of which were on the pricey side or limited availability - definitely not rejects. They have also been offering a lot more espresso blends of late (http://www.sweetmarias.com/coffee.other.blends.php). I have not tried any of these recently, but I have tried the "monkey" blend in the past and it was good.

Matthew, wind and ambient temperature can make a really big difference in roasting times with the heat gun method, so just be patient if it is windy out, and expect things to take longer.

Jess

[rotuts]

Every green been coffee you get from SM is the 'best' that Tom feels is worth his time and effort.

If he does not have it that year, its sub-par in his estimation.

the key with any way you home roast it to get a feel for reproducing the end stage of your roast.

then you can vary it a few degrees up or down. If you cant get a temp thats reproducible, look at SM area that has pictures of the color of the coffee at different temps.

If you like and really like coffee, and can roast at home, this is the only way to go.