Long time lurker, first time poster here.

Up to a month ago I was pulling great espressos, but as of lately, I have been experiencing a terrible ash aftertaste in my shots.

I regularly de-scale my silvia along with removing and cleaning the group-head. I've cleaned out my grinder ( removed burrs and cleaned with brush / compressed air). Yet I'm still getting ash flavour in my cup.

I've tried brewing at lower temperatures but that doesn't seem to fix my problem.

Is there anything on the Barista's end which would contribute to an ash flavour? I'm starting to suspect my bean provider for I swear once I smelt ash while sniffing the whole beans. I know of no other mail-suppliers in the Toronto area, so I have not ventured to other shops as of yet.

Thanks, Adam

It's virtually always the coffee. Your roaster either fell asleep during a roast or got a new batch of Brasil or other low grown bean that can't take the heat.

For now, your best bet is to dose higher, grind coarser, and let it flow faster, to get a relatively underextracted shot. This will leave some the ash in the puck, and emphasize the lighter flavors. The downside is that the shot will be taste brighter and more cutting.

If it was a one time roasting slip up, no problem; but if your roaster actually bought a coffee that roasts ashy, and isn't noticing, you should be looking for a better one.

If Jim's suggestions don't solve the problem, you can also reduce brew temp. With some specific coffees, a higher brew temp sometimes results in an ashy (not smokey, not tobacco, but ashy) aftertaste.