Are you suggesting a real cement mixer or an attachment for a drill that's used for mixing in a 5 gal pail. I think a mixer has about the right speed but not the proper fins to distribute the ingredients evenly because sausage mix is a lot dryer than a concrete mix. An attachment on a drill would work but it would beat up your food grade pails and then food safety becomes an issue. A meat mixer is the way to go.
Mixers need to Cut into, turn and knead the meat. Sausage is not liquid enough and eventually you would have the blades rolling a log in the center of the mixer without cutting ingredients into the center. Look for a used, table top 20Qt+ Hobart Mixer, Buffalo Chopper or Vertical Cutter/Mixer...JJ
I've used my cement mixer for a lot of things, cleaning brass, mixing peat, polishing/deburring metal and stone. As
jimmyJsaid about cutting into the meat and mixing the sausage would be a problem. If it was clean I don't see why it wouldn't work with say tumbling whole turkeys. If you could just figure out a way to pull a vacuum.