I was needing some sac oil and didn't have enough oil sacs thawed out, so I cut the bottom of the frozen sac off and squeezed the oil out which didn't freeze, it was more like a paste. This way is a lot easier and less messy than "milking " them. Did I discover a secret?

Secret? Yes, I think you can call it that.
It sure is interesting how some materials can be processed better than others when cold or semi frozen. My little hand grinder cuts better when Fats are cold and solid.

This spring I ground up some whole fresh oil sacs. Then ran them through a food processor with a sharp metal blade. Mixed in some preservatives, it has a nice creamy texture and fresh sac oil smell.

Now to find the best uses for sac oil? That's the Secret?? lol.

Good thinking. For my use i just grind the full sac.

I use it in a beaver lure. I tried the sac oil in a predator lure once, and it had attraction, but there were some negatives to the lure also, and I never followed up on it.