I’d been lazy and not dried my Rancilio Silvia espresso machine properly during a period of not using it for a while. To my horror, we found out some mould had developed inside the machine, which obviously made the coffee taste and smell pretty horrible. I did some frantic googling and found three suggestions to get rid of the mould:

1. Descaler with mould remover
2. Bleach
3. Vinegar

Of these, I couldn’t find any of the recommended brands online or in local shops. I tried a regular descaler solution and it seemed to do the trick, but the smell came back in a week. I didn’t like the idea of using bleach as it’s properly poisonous, and it seems bleaches that are pure chlorine aren’t to be found in London. So vinegar it was.

Ocado had the pictured strong (24%!!) pickling vinegar available. The process I used that seems to have worked was:

1. Clean the water container thoroughly, until there’s no smell left
2. Pump a full container through the machine
3. Make a strong vinegar solution (I put half the bottle in half a container of water)
4. Pump the vinegar solution through the machine until you can smell the vinegar is full through the pipes. Do this to both the coffee extruder (or whatever it’s called) and the steam pipe.
5. Switch off the machine for an hour
6. After an hour, pump the rest of the vinegar through
7. Clean the water container thoroughly, again, until there’s no smell left
8. Pump five full containers of fresh water through the machine, until there’s no smell left. Remember the steam pipe.
9. Done!

Note this process is not recommended by the manufacturers as it probably corrodes some of the internals. Do this at your own risk!