No never did fry any, never have in the past. My stuffer leaves a lot of meat in the bottom and in the stuffing tube. Could have fried some of that. By the way, this stuffer wastes alot of meat. Don't know the make but bought at Cabelas.
I make a test patty before stuffing. That way I can adjust any seasonings, which usually is adding more salt, or possibly water. It a good practice to get use to. In your case, if you bad taste was detected prior to stuffing, you would have saved using your casings. If the test patty tasted good, then you narrow down the problem that something occurred during the smoking/cooking process.
I would say most vertical stuffers do leave a'lot at the bottom, I usually freeze that bit and add it to the next batch. I was actually thinking of purchasing a dakota hydro stuffer. Anyone use these?
I have the 10 pound Dakota Water Stuffer; which they are now calling the 9 pound stuffer. It works really well, but I've only used mine about five times since I've had it, and I've had it for at least for 8 years. I don't make big batches anymore, so I find myself not using it as much. There is virtually no "waste".