A bitter or sour shot is not a broken machine — it is a dial-in signal. The fix is usually a small grind or dose change, not a new purchase.
This troubleshooting guide gives you the exact adjustments to move your espresso from harsh to balanced, whatever machine you own.
Bitter, harsh, over-extracted
Bitter espresso usually means over-extraction: grind too fine, dose too high, or shot running too long. Fix by grinding coarser, reducing dose slightly, or cutting the shot 2-3 seconds sooner.
Bitter shots also commonly come from water that is too hot — drop your brew temperature a degree or two if your machine allows it.
Sour, thin, under-extracted
Sour espresso means under-extraction: grind too coarse or shot too short. Grind finer in small steps, increase dose slightly, or let the shot run closer to 30 seconds.
Sour can also come from stale or very light beans — freshen the beans before chasing machine settings.
The dial-in loop
Change one variable at a time: grind, then dose, then time. Pull a measured shot (ratio 1:2 in 25-30s), taste, adjust one thing, repeat.
Keep a tiny notebook or an app log — espresso memory is shorter than you think, and logging turns guessing into dialling.
