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Date: 20 Sep 2007 09:53:50
From: Crabman
Subject: Question about espresso process again.

If I took fresh grounds, put them in a boiler with 1.0-1.5oz of
circulating water and pressurized it to 200psi for 25-30 seconds, Would
I make espresso? I'm beginning to think I would.

The reason I ask is I keep hearing people talk about closing the outlet
hole to build pressure to 200psi while extracting. That is essentially
the same as what I described above. If it works that way, then I now
fully grasp the espresso PROCESS.

Clay




 
Date: 20 Sep 2007 08:35:57
From: Tex
Subject: Re: Question about espresso process again.
On Sep 20, 10:16 am, Crabman <crab...@dud.net > wrote:
> Robert Harmon wrote:
> > Howdy Clay!
> > Espresso is defined as being extracted by forcing (131psi) hot water (196 -
> > 203F) through a compressed layer of ground coffee in a precise time (1ml per
> > second). What you're describing is brewed coffee, albeit coffee brewed under
> > pressure. Can this be done in 30 seconds?
>
> Certainly it can be done, but what do you end up with? Is it any good?
> does it taste like espresso?
>
> I realize you're recirculating the liquid, but how much does it matter
> in that time period?
>
> Clay

OK Clay, I gotcha now. But I'd bet that unless you then forced the
steeped mixture through the free-floating grounds you'll end up with
just weak coffee.

Pressurizing the mixture *might* extract some of the desired flavor
elements, but without the water being forced *through* (it's actually
being forced between) the grounds you'd lose the effects of the water
eroding away any surface flavor compounds that are not immediately
water soluble.

But I think your idea certainly is interesting and I'd like to see the
results of your experiment posted when you've reached noteworthy
milestones.

Tex



  
Date: 20 Sep 2007 16:08:01
From: Randall Nortman
Subject: Re: Question about espresso process again.
On 2007-09-20, Tex <r_h_harmon@yahoo.com > wrote:
> On Sep 20, 10:16 am, Crabman <crab...@dud.net> wrote:
>> Robert Harmon wrote:
>> > Howdy Clay!
>> > Espresso is defined as being extracted by forcing (131psi) hot water (196 -
>> > 203F) through a compressed layer of ground coffee in a precise time (1ml per
>> > second). What you're describing is brewed coffee, albeit coffee brewed under
>> > pressure. Can this be done in 30 seconds?
>>
>> Certainly it can be done, but what do you end up with? Is it any good?
>> does it taste like espresso?
>>
>> I realize you're recirculating the liquid, but how much does it matter
>> in that time period?
>>
>> Clay
>
> OK Clay, I gotcha now. But I'd bet that unless you then forced the
> steeped mixture through the free-floating grounds you'll end up with
> just weak coffee.

Quite untrue. I can tell you from experience that even without
pressurizing the environment, you end up with very strong coffee, if
you use the right ratio of grounds to water. This is the basic
operating principle of the AeroPress and Clover coffee makers. And it
is also, if I may tease you a bit, the operating principle of a brewer
I just "invented" and will be posting photos of sometime in the next
few weeks. (Mine is basically a poor man's Clover -- combine ground
coffee and hot water, stir briefly but vigorously, filter very quickly
under vacuum. I use approx. 50mL of water to 11-12g coffee, but other
ratios are possible. This is the basic Aeropress ratio.)

Now, is it espresso? Well, most definitions of espresso (such as the
one above) are definitions of the process, not the result, and so
pretty much nothing other than an espresso machine can make espresso
defined thusly. It is, however, espresso-strength brewed coffee.
Depending on the type of filter used, you may or may not get oils in
the cup. You will not, in any case, get the oil-water-gas emulsion
that defines the mouthfeel of good espresso. I have experimented
briefly, though, with frothing coffee concentrate with a motorized
frother, which does create a sort of emulsion. Still not espresso,
but pretty tasty.

Concentration and emulsion are not the only defining characteristics
of espresso, though. The manner of extraction affects which compounds
are extracted in what proportions. Temperature, pressure, time, and
water/coffee ratio are all factors there. I don't think anybody
really understands this chemistry in a useful level of detail (yet).

> Pressurizing the mixture *might* extract some of the desired flavor
> elements, but without the water being forced *through* (it's actually
> being forced between) the grounds you'd lose the effects of the water
> eroding away any surface flavor compounds that are not immediately
> water soluble.

That sounds like shaky science to me. Eroding compounds? I think
there could be many ways to achieve the effect you're talking about,
such as vigorous stirring or agitation.


> But I think your idea certainly is interesting and I'd like to see the
> results of your experiment posted when you've reached noteworthy
> milestones.

Results of my own experiments, different than the original poster's
hypothetical process, will be posted once I work out the kinks and
have time to photograph everything and organize it into a web page.

--
Randall


 
Date: 20 Sep 2007 08:24:44
From: Flasherly
Subject: Re: Question about espresso process again.
On Sep 20, 9:53 am, Crabman <crab...@dud.net > wrote:
> If I took fresh grounds, put them in a boiler with 1.0-1.5oz of
> circulating water and pressurized it to 200psi for 25-30 seconds, Would
> I make espresso? I'm beginning to think I would.
>
> The reason I ask is I keep hearing people talk about closing the outlet
> hole to build pressure to 200psi while extracting. That is essentially
> the same as what I described above. If it works that way, then I now
> fully grasp the espresso PROCESS.
>
> Clay

It's different. Assuming the water is up to temperature, for
effectively and instantaneously adding the dosage, following pressure
and a set time, as described. The crucial point is water is
immediately diffused across the entire dosage. A difference, then,
within the dosage subjugation to water, apart a basketed-puck's
dispersal characteristics, infusion and channeling, processes, all
occurring physically as different forms. If the latter method is most
accepted as true to an end desired, it's tempting to say the former
method is apt to be an over-exposed and -extracted result. Less
relevant to conjecture, perhaps, given timed adjustments to better
qualify the former, than convention and means available when
considered for an impracticality. Close, even good, but not quite
fully grasped for actual relevance in application, granted these few
humble observances. -Flasherly

p.s. Premier espresso producer, Illy, recently announced a new machine
being marketed, with pre-packaged coffee pods along a similar line,
intended to lower a variable for how pressurized water reacts across a
matter of grounds uniformly obstructing it.



 
Date: 20 Sep 2007 11:03:04
From: Moka Java
Subject: Re: Question about espresso process again.
Crabman wrote:
>
> If I took fresh grounds, put them in a boiler with 1.0-1.5oz of
> circulating water and pressurized it to 200psi for 25-30 seconds, Would
> I make espresso? I'm beginning to think I would.
>
> The reason I ask is I keep hearing people talk about closing the outlet
> hole to build pressure to 200psi while extracting. That is essentially
> the same as what I described above. If it works that way, then I now
> fully grasp the espresso PROCESS.
>
> Clay

I don't know. It would be something of an elaborate and expensive
experiment to try but certainly not impossible. You might end up with
coffee mud or do you plan on letting the water out during your proposed
process or is this just an infusion that you propose? Do you plan on
heating the water? Any reason you picked 200 psi? 9 bar is ~130 psi so
I'm wondering if the added 70 psi has anything to do with you proposal.
Do you think the flow of water through the grounds might have
something to do with the extraction? But what I'm really wondering is
how would this allow you to "fully grasp the espresso PROCESS"?

So set up your contraption, take good notes, pictures, videos and report
back as soon as you can.

R "a great fan of science" TF



  
Date: 20 Sep 2007 12:12:54
From: Crabman
Subject: Re: Question about espresso process again.
Moka Java wrote:
> Crabman wrote:
>>
>> If I took fresh grounds, put them in a boiler with 1.0-1.5oz of
>> circulating water and pressurized it to 200psi for 25-30 seconds,
>> Would I make espresso? I'm beginning to think I would.
>>
>> The reason I ask is I keep hearing people talk about closing the
>> outlet hole to build pressure to 200psi while extracting. That is
>> essentially the same as what I described above. If it works that way,
>> then I now fully grasp the espresso PROCESS.
>>
>> Clay
>
> I don't know. It would be something of an elaborate and expensive
> experiment to try but certainly not impossible. You might end up with
> coffee mud or do you plan on letting the water out during your proposed
> process or is this just an infusion that you propose? Do you plan on
> heating the water? Any reason you picked 200 psi? 9 bar is ~130 psi so
> I'm wondering if the added 70 psi has anything to do with you proposal.
> Do you think the flow of water through the grounds might have something
> to do with the extraction? But what I'm really wondering is how would
> this allow you to "fully grasp the espresso PROCESS"?
>
> So set up your contraption, take good notes, pictures, videos and report
> back as soon as you can.
>
> R "a great fan of science" TF
>
actually 200 was a mistake. 130 is what I meant. I wrote that while I
was thinking about temperature.

Water heated. Water let out after 30 seconds.

Clay


   
Date: 20 Sep 2007 16:05:34
From: Moka Java
Subject: Re: Question about espresso process again.
Crabman wrote:
> Moka Java wrote:
>> Crabman wrote:
>>>
>>> If I took fresh grounds, put them in a boiler with 1.0-1.5oz of
>>> circulating water and pressurized it to 200psi for 25-30 seconds,
>>> Would I make espresso? I'm beginning to think I would.
>>>
>>> The reason I ask is I keep hearing people talk about closing the
>>> outlet hole to build pressure to 200psi while extracting. That is
>>> essentially the same as what I described above. If it works that way,
>>> then I now fully grasp the espresso PROCESS.
>>>
>>> Clay
>>
>> I don't know. It would be something of an elaborate and expensive
>> experiment to try but certainly not impossible. You might end up with
>> coffee mud or do you plan on letting the water out during your
>> proposed process or is this just an infusion that you propose? Do you
>> plan on heating the water? Any reason you picked 200 psi? 9 bar is
>> ~130 psi so I'm wondering if the added 70 psi has anything to do with
>> you proposal. Do you think the flow of water through the grounds
>> might have something to do with the extraction? But what I'm really
>> wondering is how would this allow you to "fully grasp the espresso
>> PROCESS"?
>>
>> So set up your contraption, take good notes, pictures, videos and
>> report back as soon as you can.
>>
>> R "a great fan of science" TF
>>
> actually 200 was a mistake. 130 is what I meant. I wrote that while I
> was thinking about temperature.
>
> Water heated. Water let out after 30 seconds.
>
> Clay

How would you let the water out? Coffee is hygroscopic, it absorbs
water. If you saturate finely ground coffee with water it will just
stay there in the coffee unless you use some sort of pressure or force
to remove the water. The water won't just drop through. There was some
sort of espresso machine that spun the brew as if in a centrifuge but an
attempt at using the machine was reported as a messy failure as in "the
kitchen was baptized with coffee."

R "it's OK to make espresso" TF



    
Date: 20 Sep 2007 18:11:56
From: Crabman
Subject: Re: Question about espresso process again.
Moka Java wrote:
> Crabman wrote:
>> Moka Java wrote:
>>> Crabman wrote:
>>>>
>>>> If I took fresh grounds, put them in a boiler with 1.0-1.5oz of
>>>> circulating water and pressurized it to 200psi for 25-30 seconds,
>>>> Would I make espresso? I'm beginning to think I would.
>>>>
>>>> The reason I ask is I keep hearing people talk about closing the
>>>> outlet hole to build pressure to 200psi while extracting. That is
>>>> essentially the same as what I described above. If it works that
>>>> way, then I now fully grasp the espresso PROCESS.
>>>>
>>>> Clay
>>>
>>> I don't know. It would be something of an elaborate and expensive
>>> experiment to try but certainly not impossible. You might end up
>>> with coffee mud or do you plan on letting the water out during your
>>> proposed process or is this just an infusion that you propose? Do
>>> you plan on heating the water? Any reason you picked 200 psi? 9 bar
>>> is ~130 psi so I'm wondering if the added 70 psi has anything to do
>>> with you proposal. Do you think the flow of water through the
>>> grounds might have something to do with the extraction? But what I'm
>>> really wondering is how would this allow you to "fully grasp the
>>> espresso PROCESS"?
>>>
>>> So set up your contraption, take good notes, pictures, videos and
>>> report back as soon as you can.
>>>
>>> R "a great fan of science" TF
>>>
>> actually 200 was a mistake. 130 is what I meant. I wrote that while I
>> was thinking about temperature.
>>
>> Water heated. Water let out after 30 seconds.
>>
>> Clay
>
> How would you let the water out? Coffee is hygroscopic, it absorbs
> water. If you saturate finely ground coffee with water it will just
> stay there in the coffee unless you use some sort of pressure or force
> to remove the water. The water won't just drop through. There was some
> sort of espresso machine that spun the brew as if in a centrifuge but an
> attempt at using the machine was reported as a messy failure as in "the
> kitchen was baptized with coffee."
>
> R "it's OK to make espresso" TF
>

Okay. Got the hygroscopic part. I did not think of that, although I am
trying to sort out the process of espresso making. I was trying to see
if the pressure was forcing water into the grounds and the oils and
essentials out. I like the idea Robert has about vacuum. My theory is
first pressurize and then vacuum out all the goodness. Do this quickly
and at around 200deg should make superb coffee!

Clay


     
Date: 20 Sep 2007 22:30:39
From: Randall Nortman
Subject: Re: Question about espresso process again.
On 2007-09-20, Crabman <crabman@dud.net > wrote:
[...]
> Okay. Got the hygroscopic part. I did not think of that, although I am
> trying to sort out the process of espresso making. I was trying to see
> if the pressure was forcing water into the grounds and the oils and
> essentials out. I like the idea Robert has about vacuum. My theory is
> first pressurize and then vacuum out all the goodness. Do this quickly
> and at around 200deg should make superb coffee!

I am thinking that by "Robert" you mean me? I don't think Robert
(Harmon) said anything about vacuum, but I was talking about vacuum
filtering, such as the Clover brewer does. To clarify, vacuum is used
to suck water through the grounds (and the filter that holds back the
grounds). This is much faster and somewhat more efficient than drip
filtering (more efficient in terms of the amount of water retrieved),
but it is not going to do much about the water absorbed by the
grounds. My vacuumed pucks retain roughly their dry weight in water,
usually a little more. (I have not actually weighed the pucks; I
compare input water to output brew by volume and infer the amount
retained in the grounds. Evaporation losses make that a bit
inaccurate, of course, but it's quite close enough.)

--
Randall


      
Date: 20 Sep 2007 19:33:38
From: Crabman
Subject: Re: Question about espresso process again.
Randall Nortman wrote:
> On 2007-09-20, Crabman <crabman@dud.net> wrote:
> [...]
>> Okay. Got the hygroscopic part. I did not think of that, although I am
>> trying to sort out the process of espresso making. I was trying to see
>> if the pressure was forcing water into the grounds and the oils and
>> essentials out. I like the idea Robert has about vacuum. My theory is
>> first pressurize and then vacuum out all the goodness. Do this quickly
>> and at around 200deg should make superb coffee!
>
> I am thinking that by "Robert" you mean me? I don't think Robert
> (Harmon) said anything about vacuum, but I was talking about vacuum
> filtering, such as the Clover brewer does. To clarify, vacuum is used
> to suck water through the grounds (and the filter that holds back the
> grounds). This is much faster and somewhat more efficient than drip
> filtering (more efficient in terms of the amount of water retrieved),
> but it is not going to do much about the water absorbed by the
> grounds. My vacuumed pucks retain roughly their dry weight in water,
> usually a little more. (I have not actually weighed the pucks; I
> compare input water to output brew by volume and infer the amount
> retained in the grounds. Evaporation losses make that a bit
> inaccurate, of course, but it's quite close enough.)
>
I apologize for that Randall. Hope your not offended! :)

I'm not familiar with the vacuum method, it can be done. It depends on
the level of vacuum and the way you do it. I have worked with equipment
that sucked the water out of clay.

Clay........No pun intended


 
Date: 20 Sep 2007 09:49:24
From: Robert Harmon
Subject: Re: Question about espresso process again.
Howdy Clay!
Espresso is defined as being extracted by forcing (131psi) hot water (196 -
203F) through a compressed layer of ground coffee in a precise time (1ml per
second). What you're describing is brewed coffee, albeit coffee brewed under
pressure. Can this be done in 30 seconds?
--
Robert Harmon
--
http://www.tinyurl.com/mb4uj - My coffee pages.

http://www.tinyurl.com/2tnv87 - My 'Guidelines For Newbies' page.

http://www.tinyurl.com/2cr3e2 - I have things for sale here.

REPLY TO TEXAS_COFFEE AT THIS ISP EARTHLINK DOT NET
"Crabman" <crabman@dud.net > wrote in message
news:46f27c3e$0$17117$4c368faf@roadrunner.com...
>
> If I took fresh grounds, put them in a boiler with 1.0-1.5oz of
> circulating water and pressurized it to 200psi for 25-30 seconds, Would I
> make espresso? I'm beginning to think I would.
>
> The reason I ask is I keep hearing people talk about closing the outlet
> hole to build pressure to 200psi while extracting. That is essentially the
> same as what I described above. If it works that way, then I now fully
> grasp the espresso PROCESS.
>
> Clay




  
Date: 20 Sep 2007 11:16:08
From: Crabman
Subject: Re: Question about espresso process again.
Robert Harmon wrote:
> Howdy Clay!
> Espresso is defined as being extracted by forcing (131psi) hot water (196 -
> 203F) through a compressed layer of ground coffee in a precise time (1ml per
> second). What you're describing is brewed coffee, albeit coffee brewed under
> pressure. Can this be done in 30 seconds?

Certainly it can be done, but what do you end up with? Is it any good?
does it taste like espresso?

I realize you're recirculating the liquid, but how much does it matter
in that time period?

Clay