Measuring dose by weight vs volume?

Beginner and pro baristas share tips and tricks.
anne

#1: Post by anne »

This question has been plaguing me, and it seems so simple that I am not sure how to ask it. OK, so I understand the logic of using a gram scale to measure beans (especially as a newbie) to maximize consistency in pulling shots. However, when it comes to actually filling the portafilter, keeping the grinds evenly distributed and leveling them off then tamping, it seems that I'm at the mercy of VOLUME not WEIGHT. It seems that all the videos I see and instructions I read talk about different ways to ensure even distribution, and then with the beans leveled with the edge of the portafilter, how to tamp evenly, etc. So if ultimately my technique relies on volume, where does weight come in? It seems weight can only be a factor if I compress the beans to some degree or make conscious effort to "fluff" them before leveling them. But that goes against everything I have thought I learned. Hope my question makes sense.....

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another_jim
Team HB

#2: Post by another_jim »

It's a question of how to fill the basket.
-- If you weigh, you tare the basket or some auxiliary container, fill it with ground coffee until you hit the target weight, then level and tamp that fixed weight of ground coffee. This will get you within 0.1 grams of target for every dose
-- If you go by volume, you fill the basket, sweep it with either a straight or curved edge (straight= basket volume, curved, a little less than basket volume), then level and tamp. This method is good to about 1/2 gram.
-- Finally, if you go by time, there are timer grinders, that will grind for an interval preset to the nearest 1/10th second. This is good to about 1/4 gram.

Personally, I don't think the leveling method is accurate enough. Even in the best cafes, with well trained Baristas, one sees various combinations of 7 second time and 25% volume variations.
Jim Schulman

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Koffee Kosmo

#3: Post by Koffee Kosmo »

You need to tamp to the capacity of your basket that is matched to your machine

That capacity is the tamped puck should be almost touching the water dispersion screen when the group handle is locked in

This way there is no under or over dose

KK
Espresso Yourself - Home roast More
My Blog - http://koffeekosmo.blogspot.com/

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jammin

#4: Post by jammin »

KK,

In regards to your dosing protocol, do feel the "Nickel Trick" is good estimate for head space?

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Koffee Kosmo

#5: Post by Koffee Kosmo » replying to jammin »

Completely agree
And this dosing protocol is more reliable that weight

KK
Espresso Yourself - Home roast More
My Blog - http://koffeekosmo.blogspot.com/

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michaelbenis

#6: Post by michaelbenis »

I'm afraid I disagree, I find the dose is a function of the bean and grind as well as if not more so than the basket volume and indeed shape.

It is for example my own personal experience that whereas a Yirgacheffe generally works best at around 7g in my machines, a Sidamo can take a bit more quite happily. On the other hand I am a drinking a Honduran Pacamara at the moment that will very happily work with an 8-9g single and double ristretto of 15g. If I was dosing to fill the basket and leave appropriate headspace (the requirement for which in addition seems to vary from one machine to another in my experience) I simply wouldn't be getting the best out of any of the beans.

Cheers

Mike
LMWDP No. 237

zin1953

#7: Post by zin1953 »

Michael, I don't think you disagree at all -- or else I've misread the posts prior to yours. No one has mentioned the differences in beans until you. Ergo, I am presuming that all of the previous posts rely on the same beans/different dosing methods. You are the one that introduced varying your dose with different beans, and while I agree with you, I think it's a different issue than "weight vs. volume."

YMMV.

Cheers,
Jason
A morning without coffee is sleep. -- Anon.

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malachi

#8: Post by malachi »

another_jim wrote: Personally, I don't think the leveling method is accurate enough. Even in the best cafes, with well trained Baristas, one sees various combinations of 7 second time and 25% volume variations.
This is just not true among good baristas and indicates a bar that has long been since exceeded by top companies.
When I was working professionally full time I could dose by volume 10 straight times with variance (by weight) of less than 0.3g. This was, in fact, a training test originally introduced to me by Aaron de Lazzer and later adopted.
If on the bar my shot time was off by more than 2s (ie less than 10% variance) I would either chuck the shot and re-pull (if I thought it was a dose issue) or chuck the shot and adjust the grind.

And to be clear - at Stumptown I was an average barista.

Dosing by volume with practice is feasible, accurate and efficient.
It is not - to be clear - something I would recommend to most home baristas as the "with practice" assumes a lot more practice (and coffee) than is economical (or realistic).
But saying that it cannot be done in a bar scenario is untrue - and saying that "well trained" professional baristas accept variance of 25% in extraction is even more untrue.
"Taste is the only morality." -- John Ruskin

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malachi

#9: Post by malachi »

Koffee Kosmo wrote:You need to tamp to the capacity of your basket that is matched to your machine

That capacity is the tamped puck should be almost touching the water dispersion screen when the group handle is locked in

This way there is no under or over dose
1 - tamping has nothing to do with the topic. We are talking about dosing. "Tamping merely preserves your coffee bed."

2 - in some cases you want the tamped puck to almost touch, with other situations you want more headroom, and in some cases you want full contact. It depends on the coffee, your machine and your desired taste profile.

3 - "under" (or down) dosing is often desirable. "over" (or up) dosing is often desirable.

There are no absolutes.
"Taste is the only morality." -- John Ruskin

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TimEggers

#10: Post by TimEggers »

Most interesting, Chris can you elaborate on the case for a coffee needing to hit the dispersion screen?
Tim Eggers
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LMWDP #202