Under extraction - grind finer or increase dose? - Page 2

Beginner and pro baristas share tips and tricks for making espresso.
User avatar
cafeIKE
Supporter ❤

#11: Post by cafeIKE »

+1

User avatar
another_jim
Team HB

#12: Post by another_jim »

Look, I hate to interrupt this discussion of aesthetics, but under extraction has a precise physical meaning. It means less than 20% of the solids are being dissolved in the espresso. If you want more of the coffee to dissolve, you need to either grind it finer, or use less for the same amount of water, brew time, etc. Or you can do both. Dosing higher and keeping other factors equal will always reduce the level of extraction. This is physics, not art or taste.

Whether what the OP tasted is "definitely underextraction" is another question entirely. People tend to use the term for weak shots, or shots that lack depth. Neither of these proves under-extraction. The only thing strongly indicative of under extraction is too few slow dissolving ingredients in the shot. If the blend can produce caramel, or some peaty flavors, and you are not getting these, you are underextracting. Acidic flavors, bright cutting flavors like oak or lemon peel extract quickly and are not diagnostic of either under or overextraction. I used to think all dark roast flavors dissolved slowly, but this is not true either, you can get clove and blackcurrant in underextracted shots.

In other words, it's not a trivial matter to guess the solids extraction from the taste, and I'd have low confidence in any guess I make with a blend I hadn't worked. Once I know what a low dose, fine grind, long pull shot tastes like, I know what the blend is like overextracted. Similarly, a short pull shot of a coarse grind and overloaded basket will give me the underextracted taste. Once I know these, I'll be a lot happier saying what's under and overextracted in a blend.
Jim Schulman

User avatar
malachi

#13: Post by malachi »

Fair point.

So the question is, are we talking true under-extraction (as well defined above) or are we talking "under-extraction" (as commonly and perhaps incorrectly used)?
"Taste is the only morality." -- John Ruskin

User avatar
Heckie

#14: Post by Heckie »

I think Burlsube left this lengthy conversation several hours ago :D ............

User avatar
another_jim
Team HB

#15: Post by another_jim »

Chris you are probably right on that point. Unless you are willing to bake pucks or invest in a good refractometer, it may be best to just find out what low dose and high dose and high dose shots taste like, without labeling them in extraction terms.

In general, the over-extracted low dose ones will have lots of caramel and more subdued flavors, while the under-extracted higher dose ones will be less sweet but have more marked flavors both acidic and bitter based. But there's been lots of exceptions.
Jim Schulman

User avatar
malachi

#16: Post by malachi »

You know... I've never thought about it, but it would probably be a worthwhile experiment for most folks to pull a normal shot, then build the exact same shot but cut it at 2/3 extraction (by time) and at 1 1/3 extraction (again by time) and taste them all.

Obviously... this won't be a really accurate way of producing over-extraction or under-extraction in the true sense in any guaranteed way -- but as said, without investing in a refractometer it's probably the best close approximation and could at least enable people to start tasting the differences.
"Taste is the only morality." -- John Ruskin

User avatar
another_jim
Team HB

#17: Post by another_jim »

Here's the graph of shot time versus yield I recorded when baking pucks:
Image
The yield axis (Y) figures are uncalibrated, add 25%.

Go 15 seconds (post dwell) to get a drinkably underextracted shot.

Getting over-extraction by lengthening the shot time is problematic. The puck/basket geometry seems to dictate the maximum yield level. For over-extracted, you are better off down dosing and grinding fine.
Jim Schulman

User avatar
BradyButler

#18: Post by BradyButler »

another_jim wrote:...The only thing strongly indicative of under extraction is too few slow dissolving ingredients in the shot. if the blend can produce caramel, or some peaty flavors, and you are not getting these, you are underextracting. Acidic flavors, bright cutting flavors like oak or lemon peel extract quickly and are not diagnostic of either under or overextraction. I used to think all dark roast flavors dissolved slowly, but this is not true either, you can get clove and blackcurrant in underextracted shots...
Most useful thing I've read in a long time.
LMWDP #379
Carolina Espresso Services - "Quality Service for Espresso Equipment"

User avatar
BradyButler

#19: Post by BradyButler »

malachi wrote:You know... I've never thought about it, but it would probably be a worthwhile experiment for most folks to pull a normal shot, then build the exact same shot but cut it at 2/3 extraction (by time) and at 1 1/3 extraction (again by time) and taste them all.

Obviously... this won't be a really accurate way of producing over-extraction or under-extraction in the true sense in any guaranteed way -- but as said, without investing in a refractometer it's probably the best close approximation and could at least enable people to start tasting the differences.
I think this is a great thought.

Some trainers do an exercise where they dial the shot in to pull properly, then use a series of shotglasses to catch the extract in parts: the first one catches the extract from 0-10 seconds, 2nd catches 10-20 seconds, etc. The samples are then smelled and tasted, with discussion on each sample's flavor, body, sweetness, aroma, crema, intensity, bitterness, etc. That is meant to demonstrate the different extraction rates of the various components, which I believe is also helpful in diagnosing over/under extraction.

To the OP, I suspect that the question is more "my shot pulled too fast", and am in agreement with Chris's approach. Try one, then the other, and see which extraction is "best". I'd likely start with dose, because that is an easier change... but since they're already at 16g already, think grind is probably the better choice.

Jim's point is well made though.
LMWDP #379
Carolina Espresso Services - "Quality Service for Espresso Equipment"

jasonmolinari

#20: Post by jasonmolinari »

BradyButler wrote:Most useful thing I've read in a long time.
+1