What was it???

I got some softserv from a local place in West Boylston, Mass on Friday. It had lumps. I ate the first one without much thinking, but then there was another and another. They were flat chips of a greasy stuff that melted at room temp. I guess that they were some kind of fat, but not butterfat. The kid at the store knew about them but didn't know (or care) where they came from. I don't know what brand mix that they use, but I don't plan to return soon.

Are you sure they didn't slip you a frozen yogurt instead of the soft serve? I've had that quite unpleasant experience several times - to the point where I rarely ever eat soft serve any more.

It is butterfat- that is what happens when the machine needs to be changed. I used to work a roadfood place when I was younger and on really busy days where the machines were being used a lot you would get butterfat build up on the metal mechanisms and then it would get integrated into the ice cream. It's a terrible texture when you just want a nice creamy soft ice cream.