

Roast Your Coffee In Two Stages – Now With OpenCV Tricks - boyter
http://blog.chewxy.com/2014/02/13/you-should-double-roast-your-coffee-and-opencv-tricks/

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cpenner461
I've been roasting my own beans off and on for several years, the quality is
far better than anything you can get at the supermarket and even most coffee
shops (unless they are doing their own roasting). Buying green beans is quite
a bit cheaper as well, so you get the best coffee possible at the best price -
win win!

The air popper in the article is a popular low cost way to get into home
roasting, but I started with just a heavy pot and lots of stirring, hard to
keep things even. After a short while I built something pretty close to this:
[http://biobug.org/coffee/turbo-crazy/](http://biobug.org/coffee/turbo-crazy/)
Still a lot cheaper than something like the Behmor, but able to easily roast
1/2 lb at a time.

What I love the most about this is the analysis of the roast with opencv, will
definitely be trying that for my next roast!

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chewxy
author here - boyter informed me that this was front page on HN.

I'm actually seriously contemplating building a rig. I have 3 spare flashes
for my camera and my table is a frosted glass table. It should be able to give
uniform lighting to the beans for visual analysis.

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cpenner461
Nice. Trying to think through that - would you be shooting the flash through
the frosted glass to diffuse the light evenly?

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chewxy
Yup. And possibly in a product tent or something. How much did it cost for
your to build your version of the Turbo Crazy

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cpenner461
It's been a few years but I think it was on the order of $100-150.

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tdicola
There are lots of American small kitchen appliances that pull more than 1100
watts, including kettles. Most outlet circuits are rated for 15 amps so it's
not uncommon for some appliances like toaster ovens or vacuums to use 1800
watts. I think the reason most Americans don't own an electric kettle is that
tea isn't nearly as popular as coffee, and most folks use a dedicated drip or
single serve coffee brewer.

~~~
chewxy
Yup. It's also 13A in UK. I'm using 10A as a rough guide - mainly to
illustrate the power differences between AU and US. The post has now been
updated to reflect your comment. Thanks

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ScottWhigham
I loved this - this is why I love HN. Although roasting the beans in my oven
would terrify me - the chaffe could so easily catch fire, couldn't it?

I own the Behmor - I'm rather new to it (< 50 roasts). I'm happy with the
purchase however I would caution anyone interested that (a) there's a massive
learning curve (as OP points out), and that (b) even though it is marketed as
being able to roast 1 pound of coffee, you will only really get a light-to-
maybe-perhaps-kind-of-medium roast if you put a full pound of coffee in the
drum. I only learned this after going through about 10 pounds of coffee
(~20-30 roasts). I like a really dark roast - what I learned is that I can
only roast 10 ounces at a time with the Behmor. Check out the top-rated review
on Amazon - the guy says he can only roast 7-9 ounces at a time.

After looking at $800 roasters, I'd still buy the Behmor if I was new to this
and wanted a roaster. But here's the thing: to roast 10 ounces of coffee takes
about 35 minutes - you have a 15-22 minute roast followed by a 12-13 minute
cooling cycle. If you go through a pound of coffee a week (which is likely for
two adult coffee lovers), that means you'd have to spend almost an hour per
week to roast your own coffee using the Behmor. And this roast - there's about
a five minute time period in the latter/end part of the roast itself that has
to be attended. So you start your roast, come back 10-12 minutes later, wait
for the cues you need, and then you can go on with your life.

And you know what isn't great? The Behmor's temperature sensor will shut the
unit down if it's cold outside (like below 30 degrees F). When it's cold,
you'll have to get your roast prepared indoors, then take it outside, and
start the roast. And that five minute period where you have to watch your
roast? Let me tell you - it sucks to have to monitor a roast outside in 16
degree weather!

That said, after roasting my own, it's almost unfathomable to me at this point
to want to quit using the Behmor and go back to someone else's roast. I've
enjoyed the learning curve.

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cpenner461
Wow that seems like a very long time (especially on the cooling side). Using
my Turbo Crazy setup (see other comment here), I hit second crack in about 10m
(which I'd like to get pushed out to about 12m I think, but the temp control
on my convection oven is not very precise). For cooling I dump the beans into
a 2 sided perforated oven pan (I can't find an exact link, but imagine 2 of
these that attach together:
[http://www.amazon.com/dp/B002KE5OLY/](http://www.amazon.com/dp/B002KE5OLY/))
and shake it gently over a fan, they're cool in about 2-3 min. I figure on
about 15m per half pound of coffee.

FWIW I've never had chaff catch on fire, and it seems to me that my setup is
probably cranking a hotter/more direct heat than an oven would.

But yes - roasting in the cold stinks - and yet I still do it as well. :) On
the plus side, that cooling time drops to a min or so when it's 30F!

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andrewcooke
why is uneven roasting bad? if you want complexity in the coffee wouldn't a
variety of roasts give variety / depth of flavours? is there some technical
reason while all beans should be roasted the same?

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mertd
Would you like half of your steak well done and the other half rare?

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standeven
If you were to blend the entire steak together, would you notice?

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anonymoushn
Yes, it would taste like a mix of rare steak and ruined steak

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JasonCEC
If anyone here is interested in improving their home roasting, check out our
services for Quality Control and Flavor Profiling [1].

I'd be happy to set you up a free account as a home roaster, and I think
feedback from the HN community would be really helpful!

[1] www.Gastrograph.com

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cornellwright
I tried roasting my own beans once and it was a ton of work and made a lot of
smoke. I just buy 5 lbs at a time from a place on the internet which roasts
when I order and ships the same day. It tastes great and I don't have to deal
with roasting.

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2muchcoffeeman
A unit like the Behmor comes with an after burner to burn the excess smoke. So
you can home roast without the hassle these days.

A project like this is fun if you also enjoy the tinkering, but given the
markup on roasted beans, spending money on an appliance is very economical.

~~~
ScottWhigham
From my comment in this thread:

 _If you go through a pound of coffee a week (which is likely for two adult
coffee lovers), that means you 'd have to spend almost an hour per week to
roast your own coffee using the Behmor._

It just depends on what "economical" means to you, I suppose. One hour per
week roasting/managing is significant to me. If I could find a place that
would sell me just-roasted beans in 5lb or more bags, it might be worth it. I
paid $300 for the Behmor and I pay about $8-$10 per pound shipped for green
coffee. If you said, "Scott - here are some great tasting beans that we'll
roast for you right before we ship them, and they are $12 per pound", I would
sell my Behmor. At this point I've learned most of what I'll learn about
roasting coffee - now it's just a matter of spending that hour a week. If I
could pay a company $2 per week to reclaim that hour though...

~~~
cpenner461
You might want to check out Tonx ([https://tonx.org](https://tonx.org)) or
Counter Culture Coffee
([http://counterculturecoffee.com](http://counterculturecoffee.com)), both of
which do this. Haven't used either one myself, but see them mentioned a lot in
these types of conversations.

