another_jim wrote:Since you announced this, I've been trying to think of ways that would allow one to characterize more precisely how pressure variations affect taste and mouthfeel. After a lot of thought, I think the best route might be to find a coffee or roast that is undrinkable when done with a straight profile, and tasty when done with the pressure profile you like. If you can find one like that, it would be fairly clear how the profile affected the taste.

This seems to have got lost in the shuffle; and I wasn't april-fooling.

If the pressure tail off helps on bitterness, take a really woody coffee, a Tanzania, Monsooned Malabar, aged Sumatra, etc, roast it so you spend an extra minute or two between 300 and the first crack to put those wood flavors over the top, and try that. If the pressure profiling smooths out bitters, it should produce a Napoleon or 20 year old Tawny of a shot, while the flat profile will produce Uncle Fester's woodchip laced rotgut.

If it's acidity that's affected, it's even simpler. Just pull a light and fast roasted Kenya and see if its tasty or if you run to the sink.

My point is that with the right coffees, you don't need to do any super controlled blind tasting, since the results will be obvious beyond all possibility of self-suggestion or shot to shot variation. For instance, I knew I was onto something with dosing variations when the light roasts went from 17 gram sink shots to 13 gram lovelies, and I could do that as many times in a row as I pleased.

Once you have a "smoking gun" coffee like this, everything else becomes hugely easier. You can fine tune the profile using it, since the changes will be less subtle. You can learn what you are tasting for, and will be able to discern the effect on coffees that are less affected by profiling. And if you ever do blind tests, you can train the tasters' to pay attention to the right features by using the obvious coffee.

another_jim wrote: If it's acidity that's affected, it's even simpler. Just pull a light and fast roasted Kenya and see if its tasty or if you run to the sink.

Hope to have the chance to test this. I've been bummed about how dark I need to roast my favorite Kenyas to tame their acidity in espresso... Thanks, for the direction.

How are these pressure profiles created?