# Ideal espresso extraction ratio?



## CamV6 (Feb 7, 2012)

For some reason I have it in my head that the generally considered ideal rate on average is 33% although I notice I. The mat perger website he speaks of a rather general level if above 21%.

If I am right about 33% that means my generally used dose of 16.5g should yield c. 50g in the cup which us just shy of a 2 fl oz double

What ratio generally do you all aim for?


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## 4085 (Nov 23, 2012)

I know nothing about this topic really, as I am about to demonstrate! I thought a ratio of 60% meant if you weighed in 10 gms you extracted 10 gms plus 60% or 16 gms total.

60% of 16.5 gms gives a total of 26.4 gms, so why convert that back to fluid ounces?


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## Xpenno (Nov 12, 2012)

I think that extraction percentage and brew ratio are being interchanged here if I understand correctly.

When MP is talking about extraction ratios he is talking about the chemicals that he has managed to dissolve from the coffee and take through into the cup. This is calculated using grams in, grams out, the TDS of the coffee produced and then some maths.

A brew ratio is the ratio of grams coffee in basket to grams of liquid in the cup. Generally 1.5 is a good starting point for this i.e. 20g coffee > 30g espresso for example - 1.5 brew ratio.

I hope that I've understood correctly, if not then apologies if I'm teaching you how to suck eggs.


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## CamV6 (Feb 7, 2012)

Aha! It seems perhaps I knew and understood even less than I first realised!


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## Xpenno (Nov 12, 2012)

CamV6 said:


> Aha! It seems perhaps I knew and understood even less than I first realised!


Does what I said make some sense at least?

I generally use brew ratios as a recipe that you can change to affect the taste of your espresso. Other variables aside from grams in and out are temperature and time. You can then alter one of these variables at a time to change the taste of your coffee. If the coffee is sour then you might increase the brew temperature or reduce the amount of coffee you put in the basket for example.


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## Xpenno (Nov 12, 2012)

Gary or Patrick can probably explain more around the TDS and extraction ratios as they've had extended use of a refractometer which can be used to measure TDS. When MP is talking extraction ratios of 20+ he is probably referring to what's possible with the EK43 as higher extractions can generally be made with this grinder due to the uniform particle size. His three blog posts on the EK explain this in more detail if I remember correctly.


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## CamV6 (Feb 7, 2012)

Spence I thought brew ratio was g out compared to g in so for example if you put 15g in the basket and got 30g coffee out you had a brew ratio of 50%.

I seem to recall reiss of Londinium fame using 16.8g in the basket and looking for 35g out. I apologise to reiss if this is a misquote

It made me think though when I read the Mat peger site saying at least 21% ratio this would mean 75g out if you put 15g in the basket which can't be right surely?


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## The Systemic Kid (Nov 23, 2012)

Brewing *ratio*, extraction *yield* given as %

Extraction yield is measured as extracted mass divided by dry mass.

Extracted mass is measured by brewed mass times TDS (you need a refractometer to measure TDS).

So with a TDS of 1.3% and a brewed mass of 322grms you will have an extracted mass of 4.186grm

This would yield, with a dose weight of 22grms, an extraction yield of 19% (4.186grm divided by 22grm times 100)

Credit to Scott Rao for this example


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## MWJB (Feb 28, 2012)

Perger's referring to the "extraction yield", rather than the brew ratio (some folks also call this "extraction ratio" - e.g. 1:2 or 50%), or the "beverage yield" in grams (weight of the shot).

Extraction yield is the mass of the dry dose that is dissolved into the cup, described as a % of the dose - measuring it requires equipment beyond scales (coffee refractometer is popular, dehydration has been used in labs previously), but it can be very informative as coffee has been identified as being preferable within a certain range (usually, though not exclusively, 18-22%), though a specific preference point may shift with brew method or grind quality. Ext. yld measurements are used in conjuction with tasting to identify specific regions of interest.


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## Xpenno (Nov 12, 2012)

CamV6 said:


> Spence I thought brew ratio was g out compared to g in so for example if you put 15g in the basket and got 30g coffee out you had a brew ratio of 50%.
> 
> I seem to recall reiss of Londinium fame using 16.8g in the basket and looking for 35g out. I apologise to reiss if this is a misquote
> 
> It made me think though when I read the Mat peger site saying at least 21% ratio this would mean 75g out if you put 15g in the basket which can't be right surely?


Yes you are correct. I would call that specific example a 2:1 brew ratio as you are pulling about twice as much out in water than you put coffee in. I used to start off with 18g into about 30g in 30 seconds at 94deg with my royal. I would then tweak if required based on what I tasted. I would guess that my extraction percentage back then was below 15-18%.

MP is probably using 20g > around 40g-50g liquid to achieve 21% plus extraction ratios using the EK so you are looking towards 2.5:1 brew ratios. Other EK users are pushing it even more and going out to 60g which is a 3:1 brew ratio and maybe getting 22-23% extraction percentages.


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## Charliej (Feb 25, 2012)

Just to complicate this matter, isn't this where "normal" grinders start to hit a hard limit on extraction yield, so much so that some of the yields and examples that have been used and discussed around the internet aren't even relevant if you don't use an EK43 or have access to a refractometer?


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## Xpenno (Nov 12, 2012)

There you go, the guys have come to my rescue and explained it properly


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## Xpenno (Nov 12, 2012)

Charliej said:


> Just to complicate this matter, isn't this where "normal" grinders start to hit a hard limit on extraction yield, so much so that some of the yields and examples that have been used and discussed around the internet aren't even relevant if you don't use an EK43 or have access to a refractometer?


I think so, from MPs EK43 - Part 1

"We were using Mazzer Robur E's, as they are the industry standard for speed and reliability. With these grinders, we couldn't extract an espresso above 19% without A) the strength dropping too low from dilution or B) the shot tasting totally awful."


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## The Systemic Kid (Nov 23, 2012)

Key factor is degree of particle size distribution consistency. With grinders that produce a higher proportion of fines in a given mass of grinds, they will over-extract due to their relative greater surface area (counter intuitive but true) leading to more bitterness in the cup. To get an extraction yield 21% plus, you need a grinder that provides greater particle size consistency or use a micron sieve to remove the fines.


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## MWJB (Feb 28, 2012)

Charliej said:


> Just to complicate this matter, isn't this where "normal" grinders start to hit a hard limit on extraction yield, so much so that some of the yields and examples that have been used and discussed around the internet aren't even relevant if you don't use an EK43 or have access to a refractometer?


Well, all coffee beverages have an extraction yield, we can taste the yield (along with more complex flavours emanating from origin & brewing process). The refractometer backs up what we can taste, but also may point towards corrective action, where taste assessments aren't so clear. The consistency of grind affects at what point (usually a range in the order of +/-1% ext. yld) the beverage is sweetest & most balanced.

With a typical grind distribution, for coffee generally, this is commonly 18-22%, though some folk might like less than 18%, 22% isn't always going to be enjoyable.

The EK shifts the region of interest up, maybe 21% upwards, because of the more even grind distribution.

But yes, most espresso grinders clamp extraction yield lower than this at shorter brew ratios & lighter roasts.

Yield figures for a given method are certainly relevant & repeatable. Once you get a method sorted, you don't need to make constant measurements, unless something is inexplicably wrong or you are dialling in a new bean/brewer etc.

If you don't want to use a refractometer you can use dehydration methods if you have lab quality milligram scales and a few hours to kill. The coffee refractometer is a modern, labour saving device/system, allowing quick, real time readings from a few drops of coffee. Yield analysis has been practiced since the mid/early 1950's.


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## 4085 (Nov 23, 2012)

I might be wrong, but Cam, are you referring to brewed coffee or espresso extraction?


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## The Systemic Kid (Nov 23, 2012)

Brewing ratio and extraction yields are measured the same way for brewed and espresso.


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## CamV6 (Feb 7, 2012)

dfk41 said:


> I might be wrong, but Cam, are you referring to brewed coffee or espresso extraction?


Espresso extraction David.

Guys, can we dumb this down a bit for muppets like me! It's this kind of complicated techie stuff I am trying to get away from.

Let me ask the question another way.

Generally I dose at 16.5g in basket.

What g should I be looking for in the cup as a general principle, accepting of course that different beans might want a higher dose or loner or shorter pull, but as a rule thumb exercise.........?


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## 4085 (Nov 23, 2012)

16.5 gm plus 60% which equals 26.4 gms


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## Xpenno (Nov 12, 2012)

dfk41 said:


> 16.5 gm plus 60% which equals 26.4 gms


This would probably be my starting point too. 1:1.6 ratio.


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## Charliej (Feb 25, 2012)

dfk41 said:


> 16.5 gm plus 60% which equals 26.4 gms


If that doesn't give you the results you want don't be afraid to go higher or lower, although I would imagine going under a 1:1 ratio wouldn't be the best idea. Recently one home made blend I came up with to use up the Origin DSOL offering I was running 20g into 36-38g to get the kind of flavours I wanted from it.


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## CamV6 (Feb 7, 2012)

The Systemic Kid said:


> Brewing *ratio*, extraction *yield* given as %
> 
> Extraction yield is measured as extracted mass divided by dry mass.
> 
> ...


Aaaah I see well then what I am asking about in my own ham fisted way is extraction yield and not extraction ratio. Thank you.


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## The Systemic Kid (Nov 23, 2012)

CamV6 said:


> Aaaah I see well then what I am asking about in my own ham fisted way is extraction yield and not extraction ratio. Thank you.


You're not alone Brew ratios are all about weights - grind weight in relation to weight of extracted coffee. Extraction ratios are all about the strength of the coffee so you need to be able to measure the amount of total dissolved solids (TDS) in it.


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## garydyke1 (Mar 9, 2011)

16.5g - > 26.4g

Your extraction yield will depend on the TDS of the beverage.

If TDS is 10% - ie 1/10th of the liquid is 'stuff' = 2.64g

2.64 / 16.5 = 16% extraction. ie you pulled 16% of the 16.5g into your 26.4g espresso.

make sense?

10% TDS is pretty low for a conventional grinder at conventional brew ratios, but was an easy way to explain


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## ShortShots (Oct 2, 2013)

I have a basic problem with the gold cup standard, in that it was conceived on volume rather than mass. If we convert it to mass aren't we moving more towards 17.5-21.5% as opposed to 18-22%. call me picky....

In general I'm aiming for 20% for a lot of coffees, if its a light roast then 22-24% (I do have the benefit of an ek43 so its acheivable) otherwise 19% for darker


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## The Systemic Kid (Nov 23, 2012)

Finding extraction yields of under 20% for pour over - ideally around 19.5% or just below bring out the full flavour character when making Chemex. Above 20%, the light delicate flavours get drowned out by too much body IMO.


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## ShortShots (Oct 2, 2013)

I should clarify I'm talking espresso for my purposes, I do find when I'm using the chemex it tends towards slightly lower % otherwise the balance is thrown off. In saying that I've been struggling to nail a few coffees on the chemex lately. Tending towards the v60 until i get my mojo back


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## MWJB (Feb 28, 2012)

ShortShots said:


> I have a basic problem with the gold cup standard, in that it was conceived on volume rather than mass. If we convert it to mass aren't we moving more towards 17.5-21.5% as opposed to 18-22%. call me picky....
> 
> In general I'm aiming for 20% for a lot of coffees, if its a light roast then 22-24% (I do have the benefit of an ek43 so its acheivable) otherwise 19% for darker


Interesting point. But there are a couple of things to bear in mind:

The dehydration method used when the Midwest Research Institute region of interest (became the basis of the Gold/Golden cup program) was established, was a mass calculation, %TDS relative to the weight of the dose. So, not really.

The Gold Cup & CBI/CBC methodologies aimed to get coffees 'in the box', 20% target was identified by Lockhart simply (as far as I can research) because of it's geographical location midway between 18 & 22%. There is no mention of specific sensory attributes with respect to this target. Depending on how you translate the CBI "ideal" ratio, it can exit the box at anywhere from ~21.2% to 21.7%, potentially shifting the "mid point" down from 20%, if you strictly observe the TDS limits (which are admittedly somewhat elective).

Previously the National Coffee Association (not the Nordic CA) had identified 17.5% to 21.2% as a region of interest (mid point 19.4% ext yield). From what I have read the NCA study was in-house, based on the findings of the NCA brewing committee. The MRI study was an independent study, presumably following typical market research methodologies, which would be looking for results more in accordance with nationally representative tastes of the general public? This could account for a slight shift in preference, industry folk (NCA) more likely to reject bitterness & less likely to reject acidity, general public maybe the reverse (speculative)?

Nevertheless, when we're getting down to identifying points of a percent E.Y. at the outer margins, we're more looking at tipping points, rather than for the body of the ideal range. Identifying regions of interest down to this level of accuracy had only really been possible at lab level previously, but much more accessible nowadays with the VST refractometer/CoffeeTools & careful protocol. At the time of release, the CBI used lab techniques, but were mindful of the fact that they were dealing with clients in the real world - they could achieve accurate results, but intended for best practices to be achievable with everyday methods.

In my experience, for a given method, often the ideal range (based on flavour balance, rather than chart coordinates) is more like +/-1% ext yield, rather than +/-2% as per the ideal box. The EK shifts the ideal range (you identify 22-24% for light roasts, so still 23% +/- 1%), I'm not sure that anyone is as yet claiming it extends the ideal range for a given scenario?


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## The Systemic Kid (Nov 23, 2012)

ShortShots said:


> I should clarify I'm talking espresso for my purposes, I do find when I'm using the chemex it tends towards slightly lower % otherwise the balance is thrown off. In saying that I've been struggling to nail a few coffees on the chemex lately. Tending towards the v60 until i get my mojo back


Understood you were referring to espresso.


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## ShortShots (Oct 2, 2013)

MWJB said:


> Interesting point. But there are a couple of things to bear in mind:
> 
> The dehydration method used when the Midwest Research Institute region of interest (became the basis of the Gold/Golden cup program) was established, was a mass calculation, %TDS relative to the weight of the dose. So, not really.
> 
> ...


Ahh, I was going on the NCA findings. Thanks for clarifying that, I feel more at ease now. I agree with you about the +/-1%, especially when concerned with a less uniform grind. EK aside, trying to get an extraction yield of 22% would be quite a challenge using standard espresso practice, 19-20% far more achievable and better balanced


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