Nearly every espresso machine gives a poor first shot, and the reasons are physical.
Thermal equilibrium
The boiler reaches temperature long before the group head and portafilter do. Those are heavy pieces of brass that take 20 to 45 minutes.
The first shot brews into cold metal and comes out cooler than intended — thin and sour.
Standing water
Water in the group and lines has been sitting overnight, cooling and stagnating. It tastes flat.
The fix
Warm up properly — 20 to 30 minutes, with the portafilter locked in.
Flush the group for a few seconds before the first shot to clear the standing water and heat the metal.
Pull a sacrificial shot and discard it, if you want the first real one to be right.
The grinder too
The first dose of the day carries grounds retained from yesterday, which are stale. Purge a couple of grams before dosing.
Preheat the cup
A 30 ml espresso into a cold ceramic cup loses several degrees immediately.
Speeding up warm-up
A plug timer, or the machine’s own schedule function, set 30 minutes before you wake.
Running a blank shot a few minutes before brewing pushes hot water through the cold group and helps considerably.
The honest version
Most people just accept the first shot is a warm-up. It is what the sacrificial shot exists for.
Last reviewed 8 August 2026