HomeRoast Digest


Topic: Alp Calibration (5 msgs / 113 lines)
1) From: John Cramer
Hi again,
I've gotten almost charcoal beans on my new Alp, even when
the setting is at '5'. These are Yemen Mocha and Indian
Monsoon beans, so they're fairly small.
Anyway, I put a cooking thermometer in there to see how
high the temperature got. It's a mercury thermometer that
has a 400 degree maximum. I let it run for 10 minutes, to get
the top temp, then took out the thermometer. Finding the
stupid mercury was getting me, when I finally did. It was
still at 340. Figuring the decline rate and time taken, it had
to have been at 400 when it was taken out. A real oven
thermometer will be acquired tomorrow, to get a more
accurate temp, but I just wanted to see if any of you have
experience in the matter. Is 400 plus degree roasting temp
a VERY hot calibrated unit?
On another matter, I may just start pulling out the plug, in that
a couple of my roasts got too done during the "cool down"
process. Actually, I question the Alp having a bean cup. Why
in the world did they think that just pouring the beans from the
drum into a colander was too much trouble for the user? It's
more trouble having to pour both the stragglers in the drum and
the cup, than it would be for just the drum.
Blessings and a prayer for a GREAT new year to all,
John

2) From: Thom Underwood
I don't use an Alp but do watch the thermometer installed on my Hearthware
Gourmet very closely.  First crack is almost always around 390 degrees and
most roasts peak out between 430 and 440 degrees.  From there it seems to be
just how long I want to hang.  With the Gourmet I can watch the beans and I
watch for the color and the surface oil that I want.  And I now time the
event with a stop watch and record it in my notes.
I was thinking of getting an Alp but now I'm having second thoughts after
watching the chat.
Regards - Thom

3) From: coffenut
John,
I think the 400 or so inside temp is ok based upon comments from folks who
have also measured temps in roasters.  I recall the guy who invented the Alp
telling me that the heater coils can reach upward of 900F during the
process.  When we talk about calibration (and maybe that's not even the
right term), I think it has more to do with how long it takes the Alp to
reach max temp.  It's a gradual process that is electronically controlled
throughout the roast.  With what we call "hot Alps", these units seem to
reach the peak temperatures earlier in the total timed process than cooler
units.  If you're unit is producing charcoal at setting 5, your using 8oz
(weighed), not roasting in a box, etc, then I'd say you need to get a
replacement fro SwissMar.
Coffenut  :^)
<Snip>

4) From: Kathleen Tinkel
Different coffees roast at different rates, and the small-beaned varieties
- including the mochas - are likely to go faster than larger beans (a
fat-bean Sumatra, say). Mocha charcoal is easy to make!
If you are making sure to use 8 weighed ounces of green beans every time
you can calibrate your Alp - or more accurately, calibrate yourself to the
Alp, since there are no adjustments on the roaster that I know of.
I know that the numbered settings are tempting, but the only way I know of
to get consistent results is to listen for the cracks, peek at the beans
with a flashlight to see the color, and press the Cool button when I judge
they're ready. I time all this and record the crack and final times. If
after several roasts of a particular coffee I see a consistent pattern,
I'll set the Alp to the corresponding number and usually have good results.
But I still listen and look, and if things seem slower or faster, adjust
accordingly. Too many factors - ambiant temperature and humidity among them
- seem to affect the roast ever to really trust the numbers.
I bought a long-stemmed high-temp thermometer, meaning to drill a hole in
the Alp's housing and insert it during roasting, but now that I'm no longer
afraid to open the door and peek, the need seems less pressing. It would be
interesting to learn the temp-to-crack pattern, though, as you say - so I
may do that one day. (The $10 Webber grill thermometer has a good range for
coffee roasting, but it's a good idea to check it in boiling water to make
sure it's accurate. Mine was off by a dozen degrees in boiling water.)
If you really want to cool the beans by hand, open the Alp and take them
out early. But I've discovered that the built-in cooldown works fine, so no
longer struggle with it. I don't let them sit in there once the machine
stops, though - they finish better if I dump them into an aluminum pie pan
for a few minutes, then pack them up.
Kathleen

5) From: John Cramer
Thanks guys,
I called Swissmar today, and was told that the roasts ARE
at 430 degrees.
Anyway, I did get the oven thermometer today that had a
peak 500 degrees. After 13 minutes of roasting time,
I opened the unit, and found the thermometer pegged out
at about 550-575. A message was left to see what response
would be given. They are planning on sending me a
replacement unit.
You all are wonderful folks! I appreciate the concern you've
shown. Have a GREAT New Year!!
John


HomeRoast Digest