why your espresso tastes like that, a cheat sheet

pin this near the machine. change one variable at a time, always.

01
Sour, sharp, thin body
grind finer first. if that's not enough, bump dose up half a gram before touching anything else
02
Bitter, harsh aftertaste, ashy
go coarser first, then dose down, before you shorten the shot
03
Watery, gushes out under 20 seconds
coarse grind or low dose or an uneven puck. grind finer and redistribute before tamping
04
Sour and bitter at the same time
that's channeling, not a ratio problem. don't touch the grind, fix the distribution
05
No crema at all
06
One side of the portafilter spraying
channeling again. usually distribution, sometimes a worn basket
07
Shot takes 40+ seconds and barely moves
coarser, you went too far the other way
08
Puck looks dry and cracked after the pull
09
Coffee smells burnt before you even taste it
check the boiler temp isn't creeping up, or the beans are just roasted dark for this
10
Flat, dull, no acidity at all
probably stale beans more than a dial in problem. check the roast date first
11
Muddy, gritty mouthfeel
grinder's throwing too many fines. burrs might be due
12
Shot sprays out the sides of the portafilter
13
Crema disappears in under a minute
beans are past their peak, that's not a machine issue
14
You changed grind and dose at the same time and now nothing makes sense
change one thing, pull a shot, taste, then change the next. i relearn this twice a year

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