Home Roasting Interim results

ArabBeaker

New member
Sep 19, 2008
71
0
New Zealand
As a newbie to home roasting I am having to do plenty of trials to see how I like my beans, boy its been tough having to wade through mountains of freshly roasted coffee.

As already mentioned, I've had four origins available at this stage: Colombian, PNG, Sumatran and Kenyan.
My initial plan was to try and detect the differences between them, then see how different roast times affected flavour for each. My opinion is that the differences are difficult to determine, and one major reason is that I like my coffee milk based. Meaning that its hard, if not impossible to brew the same capuccino or flat white every time, so much depends on milk freshnes, foam density, temperature etc. etc.

Anyway that aside, my most obvious little discovery, and to me, easily the most important is how the beans are roasted i.e. time vs. temperature.
My crude little setup is simply a popcorn air popper, which does the trick quite well I think and roasts approximately 80 gms in about 6 minutes 30 seconds.
However I began noticing a flavour difference when the ambient air temp began to increase now that summer is approaching. The roast took less time to acheive the medium roast level that I prefer, and as this happened, the coffee was sharper, more acid and more carbonic. I found I needed to wait four days for this to dissapate. Which still resulted in great coffee, BUT I also noticed the crema became less thick and velvety after another couple of days.

I decided that 6 and a half minutes was too short a roast time. So began looking for a simple way to extend the roast time without darkening the beans. The easiest way was to reduce the weight of beans to 70 gms and try roasting first thing in the morning when it was colder. I got up to 8 minutes by doing this. Next I tried fanning cold air under the popper, in effect, forcing cold air into the intake vent. This got me another 2 and a half minutes, now I was up to 10 minutes 30 seconds to get to a medium roast, still not beginning the second crack, which is where I prefer my roast. For me, if the second crack starts, its gone just a tad too far.

The result is that, as expected, the acidity has reduced markedly and there is almost no carbonic bite after 24 hours. The coffee tastes richer yet more mellow, with a wonderful freshness and thick velvety crema that looks superb in the cup. The chocolately after taste is smooth and without any sign of sharpness.

I've built a makeshift fan induction chamber ( a fancy description for a cardboard box with a couple of holes) :oops: on which the popper sits over another hole where the air exits. I can control the amount of forced air entering the box by controlling the fan speed, thus the roast time, irrespective of the ambient air temperature.
This setup is just an easier alternative to a voltage controller where the heat of the element is controlled to slow down or speed up the roast.

My interim conclusion is that a 10 minute roast definately tastes better than 6.
I have yet to try an even longer roast time, and will report back once tried.
I fully accept that all of the above is in fact simply re-inventing the wheel, its just that nowhere have I been able to discover this info avalable within all the reading I've done on the net recently. There is plenty of info on rosting, bean colour and flavour but no instructions for us corn popper users and how to get the reults I've been after.
Arab.
 

djveed

New member
Jul 23, 2008
55
0
First off - you are a total dork - and I wish I had the foresight or intelligence to be as dorky. You will go far in your coffee career, I'm sure.

Secondly - nice job. I'm resorting to the traditional pan roast. I have no air flow control as you've done. I also think it's a great idea for you to keep such a good record as you are. I've only been using Colombian and simply tasting it to see if I like it.

I'm going to take your suggestions. Make this an all out controlled science experiment. Roast a batch and label it C1 (for cinnamon roast). Taste it and record everything 12 hours later, 36 hours later, and 60 hours later. Perhaps on the 4th day as well. Then we'll redo it for M1 (med roast) and D1 (dark roast).

Quick question - does your Colombian have a sweet taste to it?
 
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A

ArabBeaker

New member
Sep 19, 2008
71
0
New Zealand
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wish I could say, but the truth is, I can't. All I can say is, for espresso, it does make a difference how long you let the pour go.
ie. sweeter the shorter the pour. Once the pour is allowed to go past the dark stuff and into the light brown stuff it gets less sweet. But that seems to be for any origin or blend. IMO.
 

djveed

New member
Jul 23, 2008
55
0
Interesting. Maybe I'll try a ristretto of an African origin followed by a long pour of an African origin, to see if there's any difference in sweetness.
 

TAXENGINEER

New member
Dec 28, 2008
3
0
Hi everyone:
Does anyone know if those cylinder drums that fit in rotesserie a foreman or ronco are any good for roasting coffee?THEYRE ON EBAY?
Thanks in advance
 

jlyon10

Super Moderator
Feb 16, 2007
436
0
Clemmons, NC
I have one that fits on my BBQ that I really like for roasting a pound of coffee, for smaller batches I still use my Fresh Roast Plus 8
 
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