HomeRoast Digest

Topic: To Crack or Not to Crack (11 msgs / 156 lines)
1) From: Kathleen Tinkel
I've heard more than one theory about the divots (the bits knocked off
during roasting), including one that says they come from tiny insects
nestled in the bean. It would make sense that it would come from some
source of moisture (though not necessarily a bug).
Some coffees are more prone to divots than others - Yemens, for example -
and I have found them even in beans that were never taken as far as second
I do agree that you must have the cracks, at least the first. 

2) From: Jeff Wikstrom
I know from having lived in a third world country for a while that third
world products carry their fair share of bugs.  Picking through beans (the
red kind that you boil and eat, not coffee ) was a common practice for
us.  We would often find a hole from wevols.  The first time I experienced
that in home roasting, my little bug friends came to mind.  Could it be that
commercial roasters just sorter better than we do?

3) From: Kathleen Tinkel
   commercial roasters just sorter better than we do?
Maybe. Wouldn't be that hard to get rid of the divots and broken parts of
beans with a sieving process. But some coffees seem more prone to this than
others. I just roasted two batches of Zimbabwe - one just into first crack,
one 2 minutes in - which threw acres of chaff but no divots. 
It could also be a function of processing - I believe that wet processing
generally results in cleaner coffee.

4) From: Mike Gastin
My experience/understanding is that the 'plugs' or ' divots' are usually
only produced during second crack. It would be unlikely that you would get
any roasting a Zim just into or just past first crack.
I do agree that the divots would be easily dispatched with a screening
process. I have found the divots in the bottom of a $bucks bag from time to
time. I remember noticing them for the first time and wondering what they
were. (I had not started roasting, yet and was unaware of the roasting
process ...etc.)
Anyway, I have a friend that works at Chock Full O' Nuts. I know they are
not really gourmet, but I'll ask if they screen after roasting.
Mike Gastin

5) From: Kathleen Tinkel
Mike G:
   I know they are not really gourmet, but I'll ask if they 
   screen after roasting.
I doubt they roast dark enough for it to matter.
BTW - I do get divots from some beans - Timor, for example - when roasting
just barely into second crack. The Zimbabwe may need more, it's true. I
pushed it a bit today in a second batch, and think I'll go still further
next time.
So much to learn with a new roaster. My FreshRoast experiences don't
translate especially well!

6) From: Michael Rochman
Kathleen, I get no divots. Roasting mostly "Island" coffees, 
Centrals, and Kenya, plus some Yemin, etc. Take all up to just 
before 2nd crack, when I can (dark as possible with no oil).
Is it the beans, or is it the degree of roast, or is it both?
On 24 Aug 2000, at 17:09, Kathleen Tinkel wrote:

7) From: Scott
on 8/24/00 5:48 PM, Michael Rochman at mdr1000 wrote:
Roasting speed, perhaps?

8) From: Jeff Wikstrom
Do you use a fluid bed or a slow roaster?

9) From: Michael Rochman
Roasting speed?  Hot Alp?   Mike
On 24 Aug 2000, at 18:18, Scott wrote:

10) From: Michael Rochman
Alp, drum roaster.   Mike
On 24 Aug 2000, at 16:16, Jeff Wikstrom wrote:

11) From: Gary Zimmerman
I only ever see the blow plugs when I go into second crack - usually more 
than 30 seconds to one minute into second.
-- garyZ
paper-filter drip and vacuum

HomeRoast Digest