It seems that super low dosing a basket will lead to major flow increase/channeling towards the end of the shot. The puck to turns into goop. I suppose its once all the co2 has been released that this happens, though that's only a guess.

I've been using 14 to 15 gram doses in either the Espresso Parts HQ 14 or HQ 21 baskets, and I can't detect much difference between shots. These baskets appear to be identical with the exception of depth, same hole pattern.

This is with my spring lever where I pull the cup based on weight.

tekomino wrote:Try it. You'll have hard time achieving "nothing changes"

LOL

I was trying to clarify the OP question. I meant to say that if nothing changes in the ground size, etc, and the same thing that went into an 18g basket will now go into 20 and/or 22 grams, what will happen? Never meant that nothing will change in the results.

Heck, I am going to try this tomorrow. I'll sacrifice 20 grams for the sake of advancing humanity. But I have VST baskets and they are supposedly designed differently for each weight, so I don't expect it to be the same, but will be interesting to see.

In part I am getting at when our fellow enthusiasts say that they preferred "X" espresso at "Y" grams. More often than not, I will not see basket size. Would it be implied that if they said 18 grams, they used a 18 gram filter. I thought that some coffees took to updosing well. Does updosing simply mean greater than a standard 14gram shot? Or does updosing mean using more than recommended for a given basket? Vise-verse for downdosing?

That has more to do with the total dose than the basket that it is prepared in. The Italian standard for a double is 14 grams and 7 for a single. So if you use 16 grams (or anything higher than 14 grams) you are updosing. If you use less than 14 grams of coffee you are down dosing. It can also be relational to a basket size. So if I have a 18 gram basket and jam 20 grams in it, I am also updosing but most often it is a reference to using more than 14 grams of coffee in a double basket.

The Italian Espresso National Institute has a long list of criteria (7g coffee, 88C, 25sec, 25ml, yada yada) that specify Italian espresso. While these specifications represent a good starting point for espresso, I doubt that anyone here follows these criteria blindly for all coffees and all machines.

Different baskets (and groupheads) allow for different doses. For some double baskets, a 14g puck tamps so far below the rim that it is clearly a downdose. For others (I'm thinking of small diameter lever baskets), 14g represents the maximum that you can pack into the basket before the puck hits the shower screen. Claiming 14g as the standard dose for all double baskets simply does not work.

Coming back to the original question: in my experience, anything that affects espresso flow will also have an impact on taste. This includes basket geometry. If you have two baskets of different size but similar flow characteristics for a given dose, then the effect will be minimal. But if the same dose leads to different flow in different baskets, I would expect the taste to change as well.

For any given basket, doesn't updosing imply a coarser grind and/or a more ristretto shot (brewing ratio, not volume) and extracting proportionally less of the solubles? Relative to an average dose, the updosed basket should be brighter/more intense. A coffee for which updosing is recommended is presumably blended/roasted to benefit.

Switching from a 14g to an 18g basket is not updosing, any more than a double is an updosed single.