Measurement of espresso machine performance - Page 2

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MOSFET

#11: Post by MOSFET »

terryz wrote:
Ouch!

Dang I think I resemble that remark.

Other than myself with a Scace device as well as the help of Stumptown tech, Ken with his Scace device, you're right Keith.....No tools, No equipment
:shock:

Good thing Greg will be acting as the designated Temp engineer, at least this way you will be able to feel vindicated.

Espresso is many things..............One must look beyond the fog in the window to see clearly.
Took me a while to see where this thread blew to.

I'm confused. Are you and others working with Chris? I have not read a lot here lately. From what I've read about the Scace device it sounds like a good standard. Though if you're limited to 0.1 degree resolution and this machine can outperform that you need better equipment. On the other hand if the machine can do better than that then that already speaks volumes.

(than that then that? ...Sorry)

:)

Keith

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malachi

#12: Post by malachi »

Heh...

Yeah - Terry was here and ran the machine through its paces the other day.
The machine is pushing the limits of the Scace + Fluke without a doubt.
Intra-shot stability is looking really good as is inter-shot stability. Standard Deviation is looking ridiculously low.
Profile looks like a GB5 profile.


I love that I'm now seen as some sort of Luddite. Very funny given that most people in the coffee world consider me a super techie geek. Must be the decade in high tech engineering management.
"Taste is the only morality." -- John Ruskin

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malachi

#13: Post by malachi »

Sean - I could not agree more.

I think that pressure is the current frontier and better understanding of pressure (in particular stability and profile) is going to yield some great insight and results.

I'd also love to see some more effort going into the chemistry of espresso. This seems to be a serious focus in Europe whereas here in the US we seem to really be looking at the physics side nearly exclusively.

In general - I'm a huge fan of measurement. Without it we're just guessing. Measurement, to me, is one of the fundamental keys in developing a better understanding of what is going on. But fundamentally I don't believe that measurement is profoundly valuable in evaluating equipment past a certain point of usefulness. For example, if I were choosing between a Marzocco Mistral and a Synesso for a coffee bar I would not be basing that decision (at all) on measurements (other than, perhaps, dimensions). Both are sufficiently temp stable given the current understandings and goals. Now... if I were choosing between a bone stock Linea and a Synesso then yes, measurements would come into play - but not at a granular level.

To sum up - I feel like temp measurements are incredibly valuable when it comes to understanding espresso. Examples would be comparing various brew temp profiles and the results in the cup or comparing the results from a sufficiently temp stable machine to one that is not sufficiently temp stable. Once you have this level of understanding (which I assume pretty much everyone here does) then I think other factors become more valuable.
"Taste is the only morality." -- John Ruskin

Caffewerks

#14: Post by Caffewerks »

MOSFET wrote:I'm confused. Are you and others working with Chris? I have not read a lot here lately. From what I've read about the Scace device it sounds like a good standard. Though if you're limited to 0.1 degree resolution and this machine can outperform that you need better equipment. On the other hand if the machine can do better than that then that already speaks volumes.

(than that then that? ...Sorry)

:)

Keith
Actually Keith we have a huge underground espresso lab here in the great Northwest. Most of us are so damn busy tasting the coffee we forget to share the info :D

The great part about this machine and the company developing it is that they have asked for opinions. It is a rare opportunity to get in on that kind of action, so heck yeah, we are all working together to insure that when this baby goes to market, it is the best it can be for the job it is being asked to perform.

The Scace device is a great tool, that I use everyday. It allows me to bench machines with a consistency that was never before available. Use
of the device on the GS3 was simply for verification purposes. I'm kind of old school with regards to all of the technical aspects of espresso machine testing and tend to spend more time on functionality and taste of the coffee. All the statistics in the world will not change the results in the cup.

The "Holy Grail" of temperature stability has been found in the last two years, so now where do we go? Sean L. seems to think it is in the pump / pressure, and maybe he is right, all I know for sure is that allot has changed in the last two years and it is all good stuff. Statistics aside, I find shear joy and happiness in the simple fact, that someone is paying attention and doing something to raise the bar commercially.

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AndyS

#15: Post by AndyS »

lennoncs wrote:Work lately has been centered on profile generation and how to specify the profile; for instance; using arc segments /radius to specify characteristics for a given pressure segment.
It's not fair, it's not fair. :-)
-AndyS
VST refractometer/filter basket beta tester, no financial interest in the company

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AndyS

#16: Post by AndyS »

MOSFET wrote: Everything about why your coffee tastes great will boil down to temperature and pressure assuming you tamped right and your beans are good quality.
Damn, Keith, you've dug yourself a very deep hole and you're slowing lowering yourself into it. Haven't you been paying attention?
-AndyS
VST refractometer/filter basket beta tester, no financial interest in the company

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another_jim
Team HB

#17: Post by another_jim »

lennoncs wrote:Work lately has been centered on profile generation and how to specify the profile; for instance; using arc segments /radius to specify characteristics for a given pressure segment.
Use a straight line profile and an actuator made of physical matter, rather than the divine stuff -- a lot cheaper, same effect, since last time I looked, infinite rates of change were still illegal in this universe.

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malachi

#18: Post by malachi »

Sean has all the cool toys.
"Taste is the only morality." -- John Ruskin

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AndyS

#19: Post by AndyS »

another_jim wrote:Use a straight line profile and an actuator made of physical matter, rather than the divine stuff
Unfortunately, I don't have an espresso machine with an actuator made of physical matter. That kind of equipment is awfully exotic.
-AndyS
VST refractometer/filter basket beta tester, no financial interest in the company

MOSFET

#20: Post by MOSFET »

lennoncs wrote:I think we are too focused on temperature;

temperature is very important but it is only a single aspect of machine performance.


where is...

Pre-infuse pressure?
Pre-Infuse Time?
Ramp to extraction pressure?
Time at pressure?
Pressure decay or increase during shot?
Flow rate of the shot?
Pressure/ Time relationships?
Grind?
Distribution?
Roast?
Etc.


We are hung up on the temperature measurements and ignoring a whole host of other measurements that should be made to complete the picture of machine performance.

What if you have 2 back to back shots..one good, one bad...same temp...who was the culprit then?

We are trying to characterize a very complex process and make conclusions after measuring only a single aspect.


Sean
Ok. Temperature, pressure, and, if you insist, time. But I took time as a given:

Pre-infuse pressure? PRESSURE
Pre-Infuse Time? TIME
Ramp to extraction pressure? TIME/PRESSURE
Time at pressure? TIME/PRESSURE
Pressure decay or increase during shot? TIME/PRESSURE
Flow rate of the shot? TIME/PRESSURE
Pressure/ Time relationships? SIGH...
Grind? TIME/PRESSURE
Distribution? TIME/PRESSURE
Roast? BEEF? MARINATED? SOUNDS GOOD.
Etc. TIME/PRESSURE/TEMPERATURE

sorry, I'm in a silly mood. Blame it on black label.

:D :shock: :roll: :wink: :o

Keith