Oooohh snap:) great read : Low Pressure Rehash

Beginner and pro baristas share tips and tricks for making espresso.
day
Posts: 1316
Joined: 9 years ago

#1: Post by day »

Oohhhh SNAP. Tying it all together. Absolutely love this read. Thanks EspressoParts for linking to it on twitter. He ties everything we have been talking about and doing for the past 2 plus years on HB together in a very coherent and logical fashion, showing that actually, it was all correct. Lower pressure tamp, low pressure shots, freezing beans, heating beans and much much more.

https://strivefortone.com/2016/05/18/th ... re-rehash/
Yes, i you per this on an iPhone

User avatar
dominico
Team HB
Posts: 2006
Joined: 9 years ago

#2: Post by dominico »

This was a very good, but very long read: there are so many discussion points here I don't even know where to begin.
https://bit.ly/3N1bhPR
Il caffè è un piacere, se non è buono che piacere è?

day (original poster)
Posts: 1316
Joined: 9 years ago

#3: Post by day (original poster) replying to dominico »

I know. I was thinking about picking one or two to start but decided that it really just needed to be processed in it's entirety first.
Yes, i you per this on an iPhone

wsfarrell
Posts: 497
Joined: 11 years ago

#4: Post by wsfarrell »

Stopped reading at the fourth "f-ck."

Why do people have to write like that?

samuellaw178
Supporter ♡
Posts: 2483
Joined: 13 years ago

#5: Post by samuellaw178 »

dominico wrote:This was a very good, but very long read: there are so many discussion points here I don't even know where to begin.
If I may? :D

In short, he's suggesting - grind finer, dose lower, use lower pressure (ignore the 9 bar crowd), tamp softer (at 10 kg), use a heated Mythos (for higher coffee ground temperature so it reaches extraction temperature quicker), dial down the brew water temperature, and finally brew longer (40sec) - to allow more 'even' & more forgiving extraction process (less in bed channeling and more even water flow within the puck).

day (original poster)
Posts: 1316
Joined: 9 years ago

#6: Post by day (original poster) replying to samuellaw178 »

One point, I think it would make more sense to actually grind frozen and then quickly heat the ground coffee to the desired temperature-perhaps a quick sous vide after grinding (or, as I will tomorrow, give it a quick radiation bath) This may account for the mixed results last year during home testing of heated beans. Some may have taken too long to benefit at extraction.

it also suggest why so many love their caravel. Small dose size is easier to stabilize and I have heard some numbers suggesting the caravel pulls at 6-7 bar under normal usage.

I have personally done some testing with low pressure and found some wonderful cups and some awful cups. Will have to go through my process carefully and see if I worked against myself at some turn.
Yes, i you per this on an iPhone

User avatar
dominico
Team HB
Posts: 2006
Joined: 9 years ago

#7: Post by dominico »

one of my groups heads has a 7 bar spring and pulls at a lower temperature, I've had the flow cranked up and been using that group exclusively for dark roasts: silly me. Time for some tweaking.
https://bit.ly/3N1bhPR
Il caffè è un piacere, se non è buono che piacere è?

User avatar
dominico
Team HB
Posts: 2006
Joined: 9 years ago

#8: Post by dominico »

Some of this may also explain the trend of why the "declining profile: longer extraction time" shots are so popular among the lever crowd as well, even in ristretto range.
https://bit.ly/3N1bhPR
Il caffè è un piacere, se non è buono che piacere è?

samuellaw178
Supporter ♡
Posts: 2483
Joined: 13 years ago

#9: Post by samuellaw178 »

day wrote:One point, I think it would make more sense to actually grind frozen and then quickly heat the ground coffee to the desired temperature-perhaps a quick sous vide after grinding (or, as I will tomorrow, give it a quick radiation bath) This may account for the mixed results last year during home testing of heated beans. Some may have taken too long to benefit at extraction.
May work..but my first thought it'd make my routine much more fussy and can be inconsistent? Worth experimenting though. :D
dominico wrote:Some of this may also explain the trend of why the "declining profile: longer extraction time" shots are so popular among the lever crowd as well, even in ristretto range.
In that article, they're using a lower-overall flat brew pressure, as opposed to declining pressure (probably just because they can't do decreasing profile). For all we know, if they keep digging further - they might end up reinventing the wheel - the classic lever profile with declining pressure profile and then coupled with declining temp profile (more even extraction/temperature gradient within the coffee bed - to speak their language). :D It just awe me how much the lever inventor got it right in the first place (probably just a happy accident).

User avatar
aecletec
Posts: 1997
Joined: 13 years ago

#10: Post by aecletec »

I like lower pressure in my shots, but this isn't coherent or logical.
The stats are poorly justified or not disclosed.
The sampling isn't random, it's not consistent or controlled or blinded and the sample "population" characteristics aren't described or justified, neither is the type of test even mentioned.
This means the claim to significance is, plainly, rubbish.
Might as well make up the data to fit your hypothesis.
The problem is, the claim is likely to be true and we may suspect that due to anecdotes - but articles like these aren't the way to justify it.

Post Reply