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Date: 22 Aug 2007 09:55:18
From: Travesso
Subject: Flow Rate
Does pressure matter if the flow rate is correct.
Say you have 300PSI, and you adjust the portafilter exit hole to give
you 2 ounces in 20 seconds, does the pressure really matter (try to
ignore some obvious concerns)?





 
Date: 31 Aug 2007 16:55:23
From: Travesso
Subject: Re: Flow Rate
On Aug 26, 8:07 am, yuvali...@gmail.com wrote:
> > But not necessarily the same coffee. Do you like, actually, have an
> > espresso machine and make espresso? Or is all your pontificating about
> > pressure just so much farting in the breeze?
>
> > r "what I want in the cup is not in the wind" TF
>
> Make sure to not fart against the breeze.
>
> Pressure always make an extensive discussion. It doesn't mean that
> coffee is made of pressure alone. Italians say barista, machine,
> beans, roast. If the machine is standard 15 bar 1000 W, pressure
> relates to the barista only (i.E. fill-tamp, temp, on-off). Simple
> coffee-101 calculation: one divided by 4= 1/4, 1/4 divided by 3 again=
> 0.083.
> Consequence: exact pressure makes only for appr. 10% of coffee's
> taste, if the barista is not totally insane.
>
> David

I am not sure I totally agree. If the pressure is at 5 PSI, then it
will mess-up all the espresso. The same is true for 33 degree water.



 
Date: 31 Aug 2007 14:29:27
From:
Subject: Re: Flow Rate
On 28 A ustos, 00:34, North Sullivan <northwri...@bluebottle.com >
wrote:
> On Sun, 26 Aug 2007 05:07:03 -0700, yuvali...@gmail.com wrote:
> >Pressure always make an extensive discussion. It doesn't mean that
> >coffee is made of pressure alone. Italians say barista, machine,
> >beans, roast. If the machine is standard 15 bar 1000 W, pressure
> >relates to the barista only (i.E. fill-tamp, temp, on-off). Simple
> >coffee-101 calculation: one divided by 4= 1/4, 1/4 divided by 3 again=
> >0.083.
> >Consequence: exact pressure makes only for appr. 10% of coffee's
> >taste, if the barista is not totally insane.
>
> >David
>
> I have some pretty wild staff. What adjustments would you make for
> the insane?
>
> North Sullivan

After carefully following the sequence of a ca. 15 years old girl-
barista in Florence in June, I would say: culture and dedication is
doing.




  
Date: 02 Sep 2007 08:37:20
From: Moka Java
Subject: Re: Flow Rate
yuvali300@gmail.com wrote:

>
> After carefully following the sequence of a ca. 15 years old girl-
> barista in Florence in June, I would say: culture and dedication is
> doing.
>
>

OK, to get the whole picture here, not only are you an idiot with
apparently no experience with espresso machines or making espresso, you
are also a pedophile and a stalker.

R "that's just great" TF


 
Date: 26 Aug 2007 11:58:59
From:
Subject: Re: Flow Rate

> "theoretical espresso never fills the cup"

Nice motto for Starbucks.

David



  
Date: 26 Aug 2007 19:31:14
From: Moka Java
Subject: Re: Flow Rate
yuvali300@gmail.com wrote:
>> "theoretical espresso never fills the cup"
>
> Nice motto for Starbucks.
>
> David
>

Wooooooo!!!! You invoked the *$ word! Am I supposed to be insulted?
Starbucks is a very successful business. You should do so well in life.

R "but for some reason, I don't think so" TF


 
Date: 26 Aug 2007 05:07:03
From:
Subject: Re: Flow Rate

> But not necessarily the same coffee. Do you like, actually, have an
> espresso machine and make espresso? Or is all your pontificating about
> pressure just so much farting in the breeze?
>
> r "what I want in the cup is not in the wind" TF


Make sure to not fart against the breeze.

Pressure always make an extensive discussion. It doesn't mean that
coffee is made of pressure alone. Italians say barista, machine,
beans, roast. If the machine is standard 15 bar 1000 W, pressure
relates to the barista only (i.E. fill-tamp, temp, on-off). Simple
coffee-101 calculation: one divided by 4= 1/4, 1/4 divided by 3 again=
0.083.
Consequence: exact pressure makes only for appr. 10% of coffee's
taste, if the barista is not totally insane.

David




  
Date: 27 Aug 2007 16:34:21
From: North Sullivan
Subject: Re: Flow Rate
On Sun, 26 Aug 2007 05:07:03 -0700, yuvali300@gmail.com wrote:


>Pressure always make an extensive discussion. It doesn't mean that
>coffee is made of pressure alone. Italians say barista, machine,
>beans, roast. If the machine is standard 15 bar 1000 W, pressure
>relates to the barista only (i.E. fill-tamp, temp, on-off). Simple
>coffee-101 calculation: one divided by 4= 1/4, 1/4 divided by 3 again=
>0.083.
>Consequence: exact pressure makes only for appr. 10% of coffee's
>taste, if the barista is not totally insane.
>
>David
>

I have some pretty wild staff. What adjustments would you make for
the insane?

North Sullivan



  
Date: 27 Aug 2007 06:07:34
From: D. Ross
Subject: Re: Flow Rate
yuvali300@gmail.com wrote:



 
Date: 25 Aug 2007 16:21:57
From: Travesso
Subject: Re: Flow Rate
On Aug 25, 6:52 pm, Moka Java <rtwatc...@fishyahoo.com > wrote:
> yuvali...@gmail.com wrote:
> > On 24 A ustos, 17:57, "Roger Shoaf" <sh...@nospamsyix.com> wrote:
> >> "Travesso" <cpaso...@hotmail.com> wrote in message
>
> >>news:1187801718.644211.178560@e9g2000prf.googlegroups.com...
>
> >>> Does pressure matter if the flow rate is correct.
> >>> Say you have 300PSI, and you adjust the portafilter exit hole to give
> >>> you 2 ounces in 20 seconds, does the pressure really matter (try to
> >>> ignore some obvious concerns)?
> >> I suspect it would not matter as the pressure differential would give you a
> >> net same result. This however is just a speculation on my part, taste is
> >> the best gauge.
>
> > Good speculation! The resistance of ball valve will add to the
> > resistance of the coffee: GRAND RULE OF PRESSURE in any coffee
> > machine: Same Flow = Same Pressure (valid for vibe&rotary+lever).
>
> But not necessarily the same coffee. Do you like, actually, have an
> espresso machine and make espresso? Or is all your pontificating about
> pressure just so much farting in the breeze?
>
> r "what I want in the cup is not in the wind" TF- Hide quoted text -
>
> - Show quoted text -

I have several espresso machines.
As long as I stick to the 20 second shot, I am not finding a
difference in taste.



  
Date: 26 Aug 2007 14:41:24
From: Moka Java
Subject: Re: Flow Rate
Travesso wrote:
> On Aug 25, 6:52 pm, Moka Java <rtwatc...@fishyahoo.com> wrote:
>> yuvali...@gmail.com wrote:
>>> On 24 A ustos, 17:57, "Roger Shoaf" <sh...@nospamsyix.com> wrote:
>>>> "Travesso" <cpaso...@hotmail.com> wrote in message
>>>> news:1187801718.644211.178560@e9g2000prf.googlegroups.com...
>>>>> Does pressure matter if the flow rate is correct.
>>>>> Say you have 300PSI, and you adjust the portafilter exit hole to give
>>>>> you 2 ounces in 20 seconds, does the pressure really matter (try to
>>>>> ignore some obvious concerns)?
>>>> I suspect it would not matter as the pressure differential would give you a
>>>> net same result. This however is just a speculation on my part, taste is
>>>> the best gauge.
>>> Good speculation! The resistance of ball valve will add to the
>>> resistance of the coffee: GRAND RULE OF PRESSURE in any coffee
>>> machine: Same Flow = Same Pressure (valid for vibe&rotary+lever).
>> But not necessarily the same coffee. Do you like, actually, have an
>> espresso machine and make espresso? Or is all your pontificating about
>> pressure just so much farting in the breeze?
>>
>> r "what I want in the cup is not in the wind" TF- Hide quoted text -
>>
>> - Show quoted text -
>
> I have several espresso machines.
> As long as I stick to the 20 second shot, I am not finding a
> difference in taste.
>

That's no surprise. My question was directed to David,
yuvali300@gmail.com. From his latest post it is clear to me that he has
no idea what he is talking/writing about.

R "theoretical espresso never fills the cup" TF


 
Date: 24 Aug 2007 08:39:31
From:
Subject: Re: Flow Rate
On 24 A ustos, 17:57, "Roger Shoaf" <sh...@nospamsyix.com > wrote:
> "Travesso" <cpaso...@hotmail.com> wrote in message
>
> news:1187801718.644211.178560@e9g2000prf.googlegroups.com...
>
> > Does pressure matter if the flow rate is correct.
> > Say you have 300PSI, and you adjust the portafilter exit hole to give
> > you 2 ounces in 20 seconds, does the pressure really matter (try to
> > ignore some obvious concerns)?
>
> I suspect it would not matter as the pressure differential would give you a
> net same result. This however is just a speculation on my part, taste is
> the best gauge.

Good speculation! The resistance of ball valve will add to the
resistance of the coffee: GRAND RULE OF PRESSURE in any coffee
machine: Same Flow = Same Pressure (valid for vibe&rotary+lever).

David




  
Date: 25 Aug 2007 18:52:59
From: Moka Java
Subject: Re: Flow Rate
yuvali300@gmail.com wrote:
> On 24 A ustos, 17:57, "Roger Shoaf" <sh...@nospamsyix.com> wrote:
>> "Travesso" <cpaso...@hotmail.com> wrote in message
>>
>> news:1187801718.644211.178560@e9g2000prf.googlegroups.com...
>>
>>> Does pressure matter if the flow rate is correct.
>>> Say you have 300PSI, and you adjust the portafilter exit hole to give
>>> you 2 ounces in 20 seconds, does the pressure really matter (try to
>>> ignore some obvious concerns)?
>> I suspect it would not matter as the pressure differential would give you a
>> net same result. This however is just a speculation on my part, taste is
>> the best gauge.
>
> Good speculation! The resistance of ball valve will add to the
> resistance of the coffee: GRAND RULE OF PRESSURE in any coffee
> machine: Same Flow = Same Pressure (valid for vibe&rotary+lever).
>

But not necessarily the same coffee. Do you like, actually, have an
espresso machine and make espresso? Or is all your pontificating about
pressure just so much farting in the breeze?

r "what I want in the cup is not in the wind" TF


  
Date: 25 Aug 2007 15:11:02
From: Barry Jarrett
Subject: Re: Flow Rate
On Fri, 24 Aug 2007 08:39:31 -0700, yuvali300@gmail.com wrote:

>Good speculation! The resistance of ball valve will add to the
>resistance of the coffee: GRAND RULE OF PRESSURE in any coffee
>machine: Same Flow = Same Pressure (valid for vibe&rotary+lever).

only AFTER the coffee has been substantially extracted. The void area
under the brew basket and above the ball valve must fill with liquid
(collapsing the natural crema in the process) before the pressure
would be equalized in the system.



 
Date: 24 Aug 2007 07:57:06
From: Roger Shoaf
Subject: Re: Flow Rate

"Travesso" <cpasoren@hotmail.com > wrote in message
news:1187801718.644211.178560@e9g2000prf.googlegroups.com...
> Does pressure matter if the flow rate is correct.
> Say you have 300PSI, and you adjust the portafilter exit hole to give
> you 2 ounces in 20 seconds, does the pressure really matter (try to
> ignore some obvious concerns)?
>

I suspect it would not matter as the pressure differential would give you a
net same result. This however is just a speculation on my part, taste is
the best gauge.

--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.




 
Date: 24 Aug 2007 07:11:44
From: Travesso
Subject: Re: Flow Rate
On Aug 23, 8:37 pm, Barry Jarrett <ba...@rileys-coffee.com > wrote:
> On Wed, 22 Aug 2007 20:50:39 -0700, Travesso <cpaso...@hotmail.com>
> wrote:
>
> >> brew a 20 second shot at 8 bar and brew a 20 second shot at 12 bar.
> >> taste.
> >
> >That is what I have been doing. I have brewed a shot at 175PSI and
> >closed the hole up enough to have it take 20 seconds. And I have done
> >it at 130PSI for 20 seconds with the hole all the way open. I really
> >can't tell much difference. Illy says that ground coffee will
> >regulate itself if the pressure gets too high--I wonder.
>
> what do you mean "closed the hole up"?

I put in a ball valve on the bottom of the portafilter so I could
adjust the flow (the hole).



  
Date: 25 Aug 2007 15:08:56
From: Barry Jarrett
Subject: Re: Flow Rate
On Fri, 24 Aug 2007 07:11:44 -0700, Travesso <cpasoren@hotmail.com >
wrote:

>On Aug 23, 8:37 pm, Barry Jarrett <ba...@rileys-coffee.com> wrote:
>> On Wed, 22 Aug 2007 20:50:39 -0700, Travesso <cpaso...@hotmail.com>
>> wrote:
>>
>> >> brew a 20 second shot at 8 bar and brew a 20 second shot at 12 bar.
>> >> taste.
>> >
>> >That is what I have been doing. I have brewed a shot at 175PSI and
>> >closed the hole up enough to have it take 20 seconds. And I have done
>> >it at 130PSI for 20 seconds with the hole all the way open. I really
>> >can't tell much difference. Illy says that ground coffee will
>> >regulate itself if the pressure gets too high--I wonder.
>>
>> what do you mean "closed the hole up"?
>
>I put in a ball valve on the bottom of the portafilter so I could
>adjust the flow (the hole).


that's not at all the same as brewing at 8bar and brewing at 12bar.



 
Date: 22 Aug 2007 20:50:39
From: Travesso
Subject: Re: Flow Rate
On Aug 22, 9:00 pm, Barry Jarrett <ba...@rileys-coffee.com > wrote:
> On Wed, 22 Aug 2007 09:55:18 -0700, Travesso <cpaso...@hotmail.com>
> wrote:
>
> >Does pressure matter if the flow rate is correct.
> >Say you have 300PSI, and you adjust the portafilter exit hole to give
> >you 2 ounces in 20 seconds, does the pressure really matter (try to
> >ignore some obvious concerns)?
>
> yes.
>
> brew a 20 second shot at 8 bar and brew a 20 second shot at 12 bar.
> taste.

That is what I have been doing. I have brewed a shot at 175PSI and
closed the hole up enough to have it take 20 seconds. And I have done
it at 130PSI for 20 seconds with the hole all the way open. I really
can't tell much difference. Illy says that ground coffee will
regulate itself if the pressure gets too high--I wonder.



  
Date: 23 Aug 2007 19:37:34
From: Barry Jarrett
Subject: Re: Flow Rate
On Wed, 22 Aug 2007 20:50:39 -0700, Travesso <cpasoren@hotmail.com >
wrote:

>> brew a 20 second shot at 8 bar and brew a 20 second shot at 12 bar.
>> taste.
>
>That is what I have been doing. I have brewed a shot at 175PSI and
>closed the hole up enough to have it take 20 seconds. And I have done
>it at 130PSI for 20 seconds with the hole all the way open. I really
>can't tell much difference. Illy says that ground coffee will
>regulate itself if the pressure gets too high--I wonder.

what do you mean "closed the hole up"?



 
Date: 22 Aug 2007 20:00:13
From: Barry Jarrett
Subject: Re: Flow Rate
On Wed, 22 Aug 2007 09:55:18 -0700, Travesso <cpasoren@hotmail.com >
wrote:

>Does pressure matter if the flow rate is correct.
>Say you have 300PSI, and you adjust the portafilter exit hole to give
>you 2 ounces in 20 seconds, does the pressure really matter (try to
>ignore some obvious concerns)?


yes.


brew a 20 second shot at 8 bar and brew a 20 second shot at 12 bar.
taste.



 
Date: 22 Aug 2007 12:19:36
From: Robert Harmon
Subject: Re: Flow Rate
In the end all that matters is flavor. That said, if you're extracting
coffee at 20 bar (~300 psi, that's some pump you have) you're going to end
up with over extracted coffee. To arrive at the mythical god-shot (sweet &
full bodied in 25 seconds) the pressure should be adjusted to ~9 bar of
dynamic pressure (pressure in the group while permitting 1 ml of flow per
second). Then adjust the grind to a coarseness that permits 30 ml in 25 - 30
seconds. These adjustments will get you in the neighborhood of the god-shot,
from there you'll need to play around with the variables until you get the
shot you like.

Enjoy!
--
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.
"Travesso" <cpasoren@hotmail.com > wrote in message
news:1187801718.644211.178560@e9g2000prf.googlegroups.com...
> Does pressure matter if the flow rate is correct.
> Say you have 300PSI, and you adjust the portafilter exit hole to give
> you 2 ounces in 20 seconds, does the pressure really matter (try to
> ignore some obvious concerns)?
>