I'm overdosing. Who knew!? - Page 3

Beginner and pro baristas share tips and tricks for making espresso.
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malachi

#21: Post by malachi »

RapidCoffee wrote: Correct dosing depends not only on the basket, but also on the grouphead. For example, a shower screen that extends downwards into the basket will limit the headspace and impact upon the correct dose. To distinguish between basket-related and grouphead-related dose factors, I'd like to suggest the following nomenclature.
While I'm with you in general on your (thoughtful) response - I would strongly caution against the phrase "correct dosing."

IMHO there is no such thing as "correct" dosing.
There are generally accepted "rules" on dosing that could be considered "dogma" by some.
And there are generally accepted "midpoints" on dose range (on a per basket per machine basis).
I would suggest that instead of thinking "correct" think "average".
RapidCoffee wrote: Overdosing occurs when the tamped grinds hit the shower screen as you lock in, leading to channeling.
I would have to dispute this statement.
I think that overdosing results in changes to flavour ("stewed") that are non-optimal.
But I haven't seen any actual evidence that overdosing leads to channeling.

In addition - I would argue that you can (with some coffee/basket/machine combinations) updose to the point where the coffee comes into contact with the shower screen without the flavour results that indicate overdosing.
RapidCoffee wrote: Underdosing is perhaps best described as a dose that is too small to produce a decent extraction. Underdosing and overdosing produce bad pours due to improper flow through the puck, characterized by taste deficiencies (overextraction or underextraction).
I, to be honest, don't have any evidence that extremes of dose (up or down) have impact on flow that would be called "improper". They have impacts on flavour as a result of changes to extraction - but I don't see any signs that tie this to flow issues.
RapidCoffee wrote: In general, underdosing and overdosing are terms we should reserve for incorrect dosing, defined by the grouphead geometry as well as the basket. Normal dosing, downdosing, updosing - these reflect dosing choices, not necessarily right or wrong.
Agreed with, again, the exception that I would not tie this to grouphead but rather flavour results.
RapidCoffee wrote: For example, on my Vetrano I typically use a ridgeless "LM" double basket that favors doses of 16-18g with my Mazzer SJ grinder. A 14g downdose requires leveling below the rim of the basket, and a 20g updose requires compression of the grinds. On my equipment, I'd characterize doses much below 14g as underdosing, and doses much over 20g as overdosing.
The trouble is that I can think of a half dozen coffees that would probably give better flavour results (in your setup) from doses of less than 14g - and can think of at least three or four that would give better flavour results from doses of greater than 20g.
"Taste is the only morality." -- John Ruskin

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RapidCoffee
Team HB

#22: Post by RapidCoffee »

malachi wrote:IMHO there is no such thing as "correct" dosing.
There are generally accepted "rules" on dosing that could be considered "dogma" by some.
And there are generally accepted "midpoints" on dose range (on a per basket per machine basis).
I would suggest that instead of thinking "correct" think "average".
Point taken. I'm grossly oversimplifying in order to make a point about nomenclature. Nonetheless, I'm more comfortable with these dosing guidelines than, e.g., a blanket rule stating "thou shalt dose 14g" regardless of basket, machine, and coffee. I also like the idea of an "average" (or perhaps "normal") dosing range.

On a related topic, there have discussions in the past on dosing by volume vs. weight. Recently the focus has shifted to dosing by weight, perhaps due to the appearance of inexpensive 0.1g resolution digital scales. Weight is much easier than volume for making precise, reproducible measurements. But this does not necessarily mean it is the best standard for dosing.

When I think about the flow characteristics in a basket, critical factors include the size and shape of coffee particles, and how they pack together in a lattice. The weight of the particles is not particularly important. Some coffees are denser than others, perhaps due to ripeness, age, and storage conditions, and a greater mass of these beans is required to fill a basket. But I'm guessing that the level (volume) of grinds in the basket is more significant in determining flow through the coffee particle lattice than the weight.
John

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Dieter01 (original poster)

#23: Post by Dieter01 (original poster) »

Thanks for the input. I was able to make some decent espresso just now. No overdose, hehe :-)