malachi wrote:Pull a traditional ristretto (17 grams of coffee in a LM ridged double, 1.25oz in 26 seconds). Taste it.
Now pull an updosed shot (20 grams of coffee in a LM ridged double, 2oz in 28 seconds). Taste it.
Do they really taste the same to you?
I'll do some testing over the next week.
It's a different sort of brew, not necessarily just like a "traditional ristretto." The more accurate comparison would be 20 grams of coffee in a double (I'll use your "2 oz in 28 secs") and 20 grams of coffee in a
triple basket (also 2 oz in 28 secs).
While I certainly don't believe that those two (20g in a double basket vs. 20g in a triple basket) have the exactly same extraction physics going on, I don't really believe that they'll really be that different. With 9 atmospheres of pressure, the expansion of the coffee puck is being restricted by the water... it doesn't need to be crammed in to be "expansion restricted." The real expansion happens
after the extraction, when the pump kicks off and the solenoid releases the pressure. By then, it don't mattah in the cup.
What I DO think though, is that cramming that coffee in the basket does sort of create a gicleur-like flow restriction during the pressure ramp-up, which might indeed contribute to an improved extraction. In that case, a massive 21-gram updose into a standard LM double basket might prove more beneficial on a un-gicleured machine... less so on my 0.6-ers.
Another point: if updosing really achieves what it purports to, then shouldn't you be pulling 3 ounce shots? A 21-gram updose is an expansion-restricted
triple. Find me a 11-gram basket and cram 14-16 grams of coffee into it and then pull 2 ounces.
Sorry. With all due respect to the updosers... I don't buy it. FYI... we DO updose at our shop (about 19-20 g per double-shot). I just don't know if I agree with the explanations.
This is why I need time with a transparent portafilter.