Scot A. Brown published a post on 3d printed rotational extruder "Rotruder" that produces continuous stream of clay objects. The rotating parts of the extruder form a mold when they are closing together.
Interesting concept and example of mold+extruder being made by with 3d printed parts. I think it could be used with other pasty materials or even food.
I have not found any design or technical documentation.It would be interesting to see the mechanism of power transmission that turns the six mold wheels.
here are some files to make it on GrabCAD: