Well, the chocolate wasn't as rich this morning, although I still noticed a pleasing difference when moving the temperature up .6F. I think my dose, extraction time and volume where not the same this time. It was a slightly faster flow rate and I allowed a little more of the blonder portion of the shot to come through and I think that took away from the chocolate. I did 1.75 ounces in 26 seconds and I'm guessing something more like 1.5 ounces in 30 seconds will get the intense chocolate. Nevertheless, I still feel the .6F brought it closer to the chocolate and the aromas were a different and pleasing too.

I wonder if the defrosted nature has anything to do with it. It seems that the shot is behaving a bit different than the fresh beans. It starts out going slow, but around 15 seconds into the shot, I get what seems like an unusual increase in flow rate and bubbling coming out of the double spout portafilter. I don't remember that happening with the fresh beans.

Looks like I might need some more experience and time to fool around with this blend to get the chocolate again.

Ken Fox wrote:What I don't know is whether current equipment can reliably produce shots at repeatable temperature differences of 1 degree F. That would absolutely need to be established before any tasting studies could go forward. Assuming the equipment can do this, then one could test the potential of some tasters to detect this difference. Any brew temperature difference below 1 degree F probably cannot be accomplished with current equipment on a repeatable basis, and you'd have to count me as a doubter on that until I am proven wrong (which I'll acknowledge when I am).

ken

I have the data to prove that this is possible with some current equipment. Unfortunately I'm not allowed to say more than that. Hope that is good enough for you.

-Greg

AndyS wrote:Not a PhD, but I don't think the limitation is in the electronics, it's in the swirls and eddys of hot water in the machine.

Yeah, I have given some thought to physical limitations such as inlet streams, element size (physical and wattage), volume, probe placement, horizontal vs vertical boiler construction, etc. etc,. Outside of limited adjustment of probe placement though, it's all just that ... thought. I don't have the skill, materials, advanced understanding of physics, or motivation to tackle such ideas. The few individuals who possess some understanding of these things are those who aren't allowed or willing to disclose such information.

Anyway, point well made. I should be asking if anyone has numbers regarding the brew temp repeatability and error limits of the production model GS3 via Scace device. I'm just curious how meaningful a 0.3F or 0.6F change in temperature is from an accuracy standpoint.

I'm just gonna have to buy one.

Matt

roblumba wrote:Well, the chocolate wasn't as rich this morning, although I still noticed a pleasing difference when moving the temperature up .6F. I think my dose, extraction time and volume where not the same this time. It was a slightly faster flow rate and I allowed a little more of the blonder portion of the shot to come through and I think that took away from the chocolate. I did 1.75 ounces in 26 seconds and I'm guessing something more like 1.5 ounces in 30 seconds will get the intense chocolate. Nevertheless, I still feel the .6F brought it closer to the chocolate and the aromas were a different and pleasing too.

Robert,

Thanks for the reply with the details. It's the details of dosing, distribution, and extraction ratio that I give thought to before automatically attributing a taste change to a minor temp adjustment. However, when discussing the notion of just how relevant the importance of temp stability is, most people are over it ... I'm not.

gscace wrote:I have the data to prove that this is possible with some current equipment. Unfortunately I'm not allowed to say more than that.

I knew that response was coming ... quite understandable though. Thanks.


Matt

When you say, most people are "over it" do you mean that they have accepted temperature stability as a relevant factor? That's my understanding. I'm a bit surprised there are people who don't believe it.

No, I believe that most people understand that temperature matters. However, it seems that most believe that temp profiles repeatable to the precision of 0.1 to 1 degree F aren't of great consequence. They may be right, but I am not so sure.


Matt

I can agree that .3F is perhaps such a small difference that is perhaps undetectable. I usually change by .6F when I'm exploring the temperature space because .3F doesn't seem to be much difference to my taste. Nevertheless, I sometimes inch the temp up by .3F when I feel like I don't want .6F change, but just to give it a hair nudge in one direction or the other.

Matthew Brinski wrote:No, I believe that most people understand that temperature matters. However, it seems that most believe that temp profiles repeatable to the precision of 0.1 to 1 degree F aren't of great consequence. They may be right, but I am not so sure.

It's not that temperature precision is not relevant, it's just bleeding hard to achieve.

For example : take a pot of boiling water and stick in a half dozen calibrated probes at various points. Variance will exceed 0.1° several times over.

Espresso is a collection of plusses and minuses.
The age of the coffee, grind, dose, distribution, brew pressure, water temp, shot volume, not necessarily in that order.

Add in the cup temperature, geometry, interval between pull, consumption and temperature.

To reliably test temperature effect, one must minimize all of the other variables.

If you bump up the temp and love the taste is it because the humidity is up and the grind is off a bit, the coffee is a bit new / old, the dose is 15.5 instead of 15 or the cup is 5 degrees warmer / cooler? ALL? None?

As long as the espresso is damn fine and the annual sink shot is a result of forgetting to reset the timer, I'm good to go.