# an oily layer on my expresso



## visacrem (May 27, 2012)

hi.im not long started as a mobile barista and ive discoverer like an extra surface on my expresso and little brown dots when ive added milk to an americano.Have i done something wrong,ive tried filling up my boiler with water then emptying it.Is something else i can do to produce nice coffee from this old machine?


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## chimpsinties (Jun 13, 2011)

What type of machine is it?

How old is it?

How are you cleaning it?


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## lookseehear (Jul 16, 2010)

A picture would also help!


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## Spazbarista (Dec 6, 2011)

At the risk of stating the obvious, massive over extraction? If you grind less fine do you still get it?


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## MikeHag (Mar 13, 2011)

I've had this in the past with Americanos. I think there are a number of reasons.

- First is cleanliness of course, and if you can give your machine regular backflushes with (just) water throughout the day (i.e. at least hourly and whenever the machine is going to be unused for, say, 15 minutes), and have something to clean the portafilter spouts, such as a steam wand cleaning tool, then that will help avoid old oils from reaching the cup.

- Secondly, when you extract expresso you extract cellulose, carbs, oils... as I'm sure you know oil and water don't mix well. The water cannot easily dissolve the these into solution, so it suspends in the water of an Americano and can look like the cup wasn't washed properly. This is just my thinking though, not a fact. Is there a fix for this one? Not sure, but you could try different beans. What beans are you using?


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