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Date: 04 Nov 2006 06:19:35
From: Dave2012
Subject: Crema Enhancers
Hello,

I wondered if anyone here could explain to me the 'science' behind
these crema enhancers you find in machines like the Briel. My baskets
are composed of a removable filter screen which is screwed into a small
metal 'holder' (containing the crema-enhancer aka rubber seal)
underneath the basket . As near as I can figure it, for my machine
anyway, the crema enhancer underneath the basket must act as a crude
pressure valve so that coffee is not released until the pressure in the
basket builds up to a certain point. After which, from the look of my
pf setup, coffee must be squirted out of the enhancer-holder device
quite harshly and into the spouts rather than dripping out (sorry its
hard to describe without pictures).

Surely all this can do is pulverise any real crema from the coffee? I
ask because I've just switched from Illy pre-ground to freshly ground
freshly roasted coffee (after advice in an earlier post), and whilst
the coffee is much better, and the crema thicker and longer lasting, it
is still quite pale. So, whilst I'm happy (for now :)) with the coffee,
just out of interest is what I'm seeing the real thing or Briel-induced
effervescence?

Unfortunately my machine doesn't seem to work properly without the
enhancers - the coffee doesn't seem to be as good and pours quickly
with lots of grounds in the cup. I'm guessing (but tell me if I'm
wrong) that the enhancers are part of what the machine uses to build
the pressure for brewing. With the enhancers in and my current grind
I'm getting a 25-30 second double shot.

Cheers,
Dave





 
Date: 06 Nov 2006 08:00:59
From: Dave2012
Subject: Re: Crema Enhancers
I'm going to try a Solis SL70 non-pressurised filter basket which I'm
led to believe will fit Briel machines and see if that improves things.
If I can find one that is, I don't seem to be able to buy them in the
UK...

By the way my grinder is a Dualit 75002 which I believe is re-branded
in the US as Solis

Dave



 
Date: 04 Nov 2006 07:48:50
From: Dave2012
Subject: Re: Crema Enhancers
Hi Randy

Thanks for the reply. A bright shiny and 'real' espresso machine is on
the (distant) horizon when i get some 'real' money! I tried grinding
one stop finer than with the 25 second shot grind but it choked the
machine. I'll try again though after giving everything a good clean.

Dave



 
Date: 04 Nov 2006 07:38:26
From: Randy G.
Subject: Re: Crema Enhancers
"Dave2012" <davecorbett2012@googlemail.com > wrote:

>Hello,
>
>I wondered if anyone here could explain to me the 'science' behind
>these crema enhancers you find in machines like the Briel.
>
My thought with those is that they do not really increase the pressure
used to brew the coffee. The reason I say that is that they are
located under the filter basket. The water force used for brewing is
the difference between the pressure above the coffee puck and the
pressure below the coffee. If the pressure below the coffee is 130psi
and the pressure above the coffee is 135psi, then an additional 1psi
applied above the coffee results in a brewing pressure of 1 psi. So
what you get is an artificial resistance to the flow of the water. The
coffee itself is not really resisting the water's flow as it would in
a "real" machine.

>Surely all this can do is pulverise any real crema from the coffee?
>
They sort of do- they emulsify some of the oils and froth up what air
or gasses are present to make a sort of crema-like stuff.

I
>ask because I've just switched from Illy pre-ground to freshly ground
>freshly roasted coffee (after advice in an earlier post), and whilst
>the coffee is much better, and the crema thicker and longer lasting, it
>is still quite pale.
>
Grind finer. Once I got my details in order, my crema became dark,
thick, and delicious. The crema I produce with Silvia at the end of
the shot is darker than I see in the local coffee shops... but that
ain't saying much.

>So, whilst I'm happy (for now :)) with the coffee,
>just out of interest is what I'm seeing the real thing..
Not really
>... or Briel-induced effervescence?
basically, yes.

>Unfortunately my machine doesn't seem to work properly without the
>enhancers - the coffee doesn't seem to be as good and pours quickly
>with lots of grounds in the cup.
>
Uchhh

> I'm guessing (but tell me if I'm
>wrong) that the enhancers are part of what the machine uses to build
>the pressure for brewing. With the enhancers in and my current grind
>I'm getting a 25-30 second double shot.
>
Try a new machine... that should solve it.. ;-)


Randy "time for the scientists to toss artificial bricks" G.
http://www.EspressoMyEspresso.com




  
Date: 04 Nov 2006 12:17:19
From: Jack Denver
Subject: Re: Crema Enhancers

"Randy G." <frcn@DESPAMMOcncnet.com > wrote in message
news:eacpk2di18afj6l7gej46c8oq2v0ht1mbf@4ax.com...
> "Dave2012" <davecorbett2012@googlemail.com> wrote:
>
>>Hello,
>>
>>I wondered if anyone here could explain to me the 'science' behind
>>these crema enhancers you find in machines like the Briel.
>>
> My thought with those is that they do not really increase the pressure
> used to brew the coffee. The reason I say that is that they are
> located under the filter basket. The water force used for brewing is
> the difference between the pressure above the coffee puck and the
> pressure below the coffee. If the pressure below the coffee is 130psi
> and the pressure above the coffee is 135psi, then an additional 1psi
> applied above the coffee results in a brewing pressure of 1 psi. So
> what you get is an artificial resistance to the flow of the water. The
> coffee itself is not really resisting the water's flow as it would in
> a "real" machine.


But it does slow down the flow rate enough to keep the coffee in contact
with the water for a decent amount of time. Without it (and with an
incorrect or poor grind and/or stale coffee, you might get a 10 second shot.
The main function of these devices is to enable you to brew SOMETHING
espresso-like with stale/badly ground coffee instead of a big thin watery
cup that even an amateur would discard.
>
> I
>>ask because I've just switched from Illy pre-ground to freshly ground
>>freshly roasted coffee (after advice in an earlier post), and whilst
>>the coffee is much better, and the crema thicker and longer lasting, it
>>is still quite pale.
>>
> Grind finer. Once I got my details in order, my crema became dark,
> thick, and delicious. The crema I produce with Silvia at the end of
> the shot is darker than I see in the local coffee shops... but that
> ain't saying much.
>>
> Try a new machine... that should solve it.. ;-)


I'm betting he needs a new grinder, not a new machine. He didn't mention
what kind of grinder he is using but I'm guessing it's a bad one.

>
>
> Randy "time for the scientists to toss artificial bricks" G.
> http://www.EspressoMyEspresso.com
>
>