HomeRoast Digest


Topic: Cold water brewing [[ was +Re: Get a horse]] (4 msgs / 232 lines)
1) From: John Abbott
Good point David. I've had cold brewed coffee and it was great.  So now I'm
wondering along with you.  I do know that the temperature really matters on
hot brewed - but why is cold brewed so good?

2) From: Terry Stockdale
I did the Toddy thing about 15 years ago, because we had hot water spouts 
on the water fountains at the office.  At the time, I thought that the big 
bucket of beans at the coffee shop meant that they were fresh.  Most of my 
coffee was Community Coffee, imported from Louisiana into Houston.
I liked its extreme smoothness.  However, with that smoothness came a a cup 
of coffee that had not one bright note too it.  Still, it tasted better 
than the Mr. Coffee stuff.
I would take a pint jar of the concentrate with me to work every day.  The 
final straw came one day, when I filled my cup 1/3 of the way, started to 
leave my office, and the phone rang.  I answered it.  Sat 
down.  Talked.  And drank a sip of "coffee."
I've still got the Toddy.  Maybe I'll try it again one day.  Anyone think 
the 15 year old felt filter might still be good.  Maybe I ought to buy a 
new one first.  If not, I can always try it with Robusta.
At 10:23 AM 1/30/2003 -0600, you wrote:
<Snip>
  Terry Stockdale --http://www.dadstoy.net--  Baton Rouge, LA
6.5 billion kilograms of coffee are grown each year -- but, I'm picky!
          Monkey + HIP + Rocky + Silvia = Espresso
homeroast mailing listhttp://lists.sweetmarias.com/mailman/listinfo/homeroast

3) From: Ed Needham
Since taste is so purely subjective, any answer to this question will
probably stir debate, but hey, what the heck.
Quick answer first...
Extraction is a process that involves time and energy.  That energy can be in
the form of heat, agitation or pressure.
I've never had cold brewed coffee.  Sun tea is good, and I can imagine the
comparison to cold brewed coffee to be similar, but I would think that there
may be extracted flavor/aroma components that differ in both, as compared to
their heat-brewed counterparts that make them taste different.  Not that
those differing components are bad.  Possibly some are the undesirable flavor
components that are best left out.
Extraction of some flavor/aroma components might occur with less time and
energy than others.  The difficult components might not extract unless the
temperature is higher than a certain point, or energy in the form of
agitation or pressure is sufficient to release them.  Again, a time and
energy issue, on a continuum, with a release threshold for each component.
The extraction threshold is the lowest temperature/pressure/agitation that
components absolutely will not budge, no matter how much time they are given
to extract.  The high limit is that point where time/temp/agitation/pressure
is sufficient to allow the nasty taste components to begin seeping in so that
they can be perceived.
Liken it to washing dishes.  Some dirty dish components dissolve easily in
water and some take quite a bit of work to remove.  Ice cream will dissolve
on a bowl placed in either cold or hot water.  Hot will dissolve it faster,
but given enough time, and with sufficient agitation, the plate will be clean
of ice cream in any temperature water.  Now a greasy plate is another issue.
You could probably soak a really greasy plate in cold water all day and maybe
all week (yuck), and it will still be greasy.  Cold water will not easily
remove grease.  But if I pressure washed it with 3200 psi powerwasher, cold
water would clean the plate.  If I rubbed the plate sufficiently with a
dishcloth (maybe for a few hours) in cold water, the plate would eventually
come clean.
Coffee has easily dissolved flavor/aroma components and more difficult to
dissolve components.  Some flavors might be bitter or objectionable if
allowed to extract.  Some aromas might smell like a wet dog if extracted.  So
there is a fine balance between time/temperature/agitation and pressure in
the extraction process.  My guess is that any of the three forms of energy
can be interchanged to achieve different extraction rates for specific
components.  Possibly why an americano tastes so different than drip brewed
at the same strength and with the same bean.
Hey, I'm just thinking out loud.  I hope some of this makes sense.
Ed Needham
To Absurdity and Beyond!http://www.homeroaster.comed
****************************************
**********************************************

4) From: Henry C. Davis
Having cold extracted a fair amount of coffee, I would have to say most of
what you said makes sense. What you extract cold will  not be the same as
brewing it hot, thus to get good cold brewed or cold extract you would have
to do a fair amount of fiddling around. What you learn from brewing a
particular coffee hot is only going to be an indicator of where to start
experimenting when using cold (or room temp) water. I have found that a
combination of time and a small amount of pressure makes the best extract,
and probably would make better cold brew. I have been surprised by what
flavors I recognize in a cold extract from a particular bean when it has
been brewed hot and the ones that are not there. I have yet to come up with
any kind of reliable guide to what is and isn't there in a cold extract, but
I am working on it. What I have noticed is that you don't get many
characteristics in a cold extract that are not, to some degree, in the hot
brew, but the hot version may well have characteristics not found when cold
brewed.


HomeRoast Digest