Stuggi wrote:I think what you're doing here is dissolving old oils with new oils, thus removing any rancid coffee oils from the machine.
Unfortunately this has the ring of truth. But the implications are ugly. As in, how long does the machine have to sit before the coated coffee oils get nasty? Sigh. Looks like I may need to rethink my cleaning regimen.

Thanks, Ian.
Whale wrote:I find that because the dish detergent will leave a taste to it that I can taste on the first "push" after the soap has gone in. I never could completely rinse that taste out.
I have heard others complain about residual soap taste, but I have to wonder if this is truly a factor. Detergents are formulated to dissolve easily in water. Let's say a thorough rinse removes 99% of the detergent in your coffee or tea pot. After three rinses, you are down to one part in a million. After six rinses (which we used for biochem lab glassware, back in my former life), it's one part in a trillion.
It's possible that dish detergent adheres to certain materials, and is only released in the presence of coffee or tea. But that seems unlikely for glass and most metals (dunno about organics like plastics).
One suggestion: dilute the dish detergent before squeezing it on your glassware. You don't need much. As Dave said, a couple of drops is sufficient for a thorough cleaning.