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On "bitterness" and "over extraction"

8.2K views 34 replies 7 participants last post by  funinacup  
#1 ·
Related to that other thread about high extraction and sweetness...

Can somebody tell me why I can with the EK do stupidly long brew times with fine grinds and not get something that tastes like arse (in my case, toning the acidity of that Square Mile from Kenyan right down and giving me a cup of "GIMME MORE" juice), and yet when I mention to this to one of my tame baristas they pull their face and go "won't that be super yuck?"

Could they also manage such things on their gear? Surely when you're going for super extraction you're always going get there if you leave it long enough even if your grinder is crap? Or do they fall short into that weird valley of bitterness unable to climb out the other side? Or is it just that you also need to use really good coffee for this sort of thing or run the risk of artifacts like roastiness and such and that's what we've always been used to? Why would one grinder taste good at 21% and another not? The wrong few %?

I'm looking for an explanation so rather than being looked at as if I'm stooooopid in the coffee shop I can say "well.... this is why my super long aeropress soak doesn't taste bitter"

This is similar to the whole coffee shot thing I guess, except there is finite time involved there and no doubt that weird uncanny valley?
 
#5 ·
Are we really still at the point where we just go "hand wave", it's the EK43

[edit]

I just don't feel as though I have a suitable enough answer when questioned on my recipes by baristas, and as a result I get patronised because they've never had a proper EK43 shot or filter (Hell, I've barely managed many of those).

"It just does" is great and all, but as far as they're concerned I might as well be talking out of my arse.
 
#6 ·
High extraction only equals sweetness if it is even. It's easy enough to get a drip brew to 23-24% with just about any grinder, though most with a less even particle distribution will be sweetest (for that design) ~19-21%.

You're not always going to hit a super high extraction, it's not a given.

Immersions can be pushed up to their limit & taste sweet, but the extraction isn't as aggressive, nor quite as efficient as drip/espresso (percolation). A long steep in any brewer is going to be hard to overextract (by taste, not necessarily the %) as long as you have a declining temperature profile. Put 20g of coffee in your Aeropress, add as much, or as little water as you like, leave it to steep & when it hits 10%TDS jump on to your hoverboard, whizz over, and show me your holographic projection of your wristwatch/coffee refractometer/molecular transportation device! :)

We are used to the idea that bitterness has a single, easily definable cause - it doesn't.

Some beans are easier to extract, as are the same beans roasted, or processed differently, but your EY target is more driven by grind distribution than bean quality per se.

The coffee shot thing is essentially treating an espresso machine as a 1 cup, flat bed, pressurised drip brewer - If you can hit 23% with an EK espresso at 2.35:1 ratio, by grinding coarser you should be able to hit that same extraction even more easily at much longer brew ratios...theoretically, down to any TDS, pretty much. They used to have a thing called a caffe crema, a long shot pulled on an expresso machine to replicate a filter coffee...similar idea to the coffee shot, but perhaps not aimed a producing the same sweet & highly targeted result. There have also been fast brew ESE pods & lungo capsules too. The long coffee from an espresso machine isn't directly related to high extraction, more to target strength, but the more water you pass through a puck/bed the better your chances of a high extraction.
 
#8 ·
MWJB said:
H A long steep in any brewer is going to be hard to overextract (by taste, not necessarily the %) s, add as much, or as little water as you like, leave it to steep & when it hits 10%TDS jump on to your hoverboard, whizz over, and show me your holographic projection of your wristwatch/coffee refractometer/molecular transportation device! :)
Granted.

We are used to the idea that bitterness has a single, easily definable cause - it doesn't.
Okay - that's a good sentence, I can use and remix that sentence for great good.

The coffee shot thing is essentially treating an espresso machine as a 1 cup, flat bed, pressurised drip brewer - If you can hit 23% with an EK espresso at 2.35:1 ratio, by grinding coarser you should be able to hit that same extraction even more easily at much longer brew ratios...theoretically, down to any TDS, pretty much. They used to have a thing called a caffe crema, a long shot pulled on an expresso machine to replicate a filter coffee...similar idea to the coffee shot, but perhaps not aimed a producing the same sweet & highly targeted result. There have also been fast brew ESE pods & lungo capsules too. The long coffee from an espresso machine isn't directly related to high extraction, more to target strength, but the more water you pass through a puck/bed the better your chances of a high extraction.
Yeah got that - the finite time thing here makes this easy to understand.

Ta - is useful.
 
#11 ·
MWJB said:
Sorry, you lost me there?
I mean - a whole bean has a total soluble content of 24-36%, the grinder does not change this - right? Unless we are saying that by bashing up the beans into tinier pieces we expose more of this soluble content and that with bigger bits of bean it's just impossible to dissolve it as fully - even with "infinite" time.
 
#12 ·
robashton said:
Yeah I get that - my point is that with every grinder this is the same number
"your EY target is more driven by grind distribution than bean quality per se."

Different grinders have different grind distributions = not tasty at 19% ey plus ( bitter )
 
#17 ·
[MENTION][/MENTION]

garydyke1 said:
Any 'fines' are similar in size to the 'rocks'
But they're not - that's the latest thing from Perger or whatever, there are actually way more fines and they're absolutely tiny tiny and that's where all the flavour comes from - I feel as though there is no way you've missed this and therefore I've missed something here too.
 
#18 ·
robashton said:
But they're not - that's the latest thing from Perger or whatever, there are actually way more fines and they're absolutely tiny tiny and that's where all the flavour comes from - I feel as though there is no way you've missed this and therefore I've missed something here too.
So far supposition ?? I know he talks off it but is anything published yet

Plus his coffee is roasty
:)
 
#19 ·
robashton said:
[MENTION][/MENTION]

But they're not - that's the latest thing from Perger or whatever, there are actually way more fines and they're absolutely tiny tiny and that's where all the flavour comes from - I feel as though there is no way you've missed this and therefore I've missed something here too.
x = fines

X = rocks

Robur :

[-x------------X--]

EK :

[-x----------X--]

small x is nearer large X with the EK
 
#20 ·
My understanding is that there are way more fines so you need less time on the brew, and somehow magically without trying the EK43 and it's largely even particle distribution size means that with spro it gushes through faster (so you grind finer *and* get more fines) and these two facts work together entirely by coincidence.
 
#21 ·
robashton said:
My understanding is that there are way more fines so you need less time on the brew, and somehow magically without trying the EK43 and it's largely even particle distribution size means that with spro it gushes through faster (so you grind finer *and* get more fines) and these two facts work together entirely by coincidence.
You are always brewing to the rocks, getting them to be tasty. With other grinders this means the 'fines' have gone way too far.

(in my head)
 
#22 ·
garydyke1 said:
You are always brewing to the rocks, getting them to be tasty. With other grinders this means the 'fines' have gone way too far.

(in my head)
Is it possible to get those fines to go too far with the EK then? And get this bitterness - I've still not managed, even when I accidentally do 90s ristretto with new beans.*

[edit]

Also I can get behind this notion even more, because the even particles, the fast flow rate, the tightening of the grind, the faster the rocks then get brewed also.

[further edit]

*note: this tastes like arse, just not "bitter" in the sense I'd expect in my experience at coffee shops when they screw up - beans maybe?
 
#23 ·
robashton said:
Is it possible to get those fines to go too far with the EK then? And get this bitterness - I've still not managed, even when I accidentally do 90s ristretto with new beans.

[edit]

Also I can get behind this notion even more, because the even particles, the fast flow rate, the tightening of the grind, the faster the rocks then get brewed also.
Espresso wise - there is definitely an interaction between fines and rocks in terms of flow rates. Perhaps the actual shape of the particles is somehow different too (in the same way conics v flats )

I note you use beans which are not 'murdered' unlike Perger
:p
Any references to bitterness in his blogs I take with a pinch of salt
 
#24 ·
garydyke1 said:
I note you use beans which are not 'murdered' unlike Perger
:p
Any references to bitterness in his blogs I take with a pinch of salt
Yeah... getting this feeling.

With some of my local beans it was impossible *not* to get bitter/roasty/nasty flavours, presumably because it's hard to do a low EY with the EK.

I feel as though I need to get a cheap Mazzer and spend some time with it to learn a bit more about the "how the other side does it"
 
#25 ·
robashton said:
Is it possible to get those fines to go too far with the EK then? And get this bitterness - I've still not managed, even when I accidentally do 90s ristretto with new beans.*

[edit]

Also I can get behind this notion even more, because the even particles, the fast flow rate, the tightening of the grind, the faster the rocks then get brewed also.

[further edit]

*note: this tastes like arse, just not "bitter" in the sense I'd expect in my experience at coffee shops when they screw up - beans maybe?
I would like to see the particle distribution info for the EK new coffee burrs, only ever seen old