Channeling

Water finding weak paths through the coffee bed instead of extracting the puck evenly.

Filed under

Before the water hits

What it means

Water finding weak paths through the coffee bed instead of extracting the puck evenly. It explains why a shot can taste both sour and bitter at the same time — some coffee is underextracted, some is overextracted, and the cup never settles into balance. Blaming the grinder alone is the common mistake.

Keep going

Where this leads

Each one pushes this into the cup, compares it, or helps you act on it.

Before the water hits

Distribution

Weak paths usually start with uneven density before the shot even begins.

Level the coffee deliberately before tamping.

Before the water hits

Puck

Channeling is a puck problem before it becomes a taste problem.

Think of the puck as the extraction environment, not just the spent material left after the shot.

Tools that help you see mistakes

Naked Portafilter

Use a bottomless basket when you want to see the fault instead of guessing it.

Use a bottomless portafilter when dialing in or training, even if you return to a spouted one for service.

What people mean when they say "extraction"

Espresso Extraction

Then connect the fault back to why the cup tastes sour and bitter at once.

Separate extraction from strength in your thinking. One asks how much was dissolved, the other how concentrated the drink feels.