I have always had the best luck with chicken liver. I cut off a large chunk of UNDAMAGED liver (usually half a liver) and using a snap swivel, I remove the hook and then I run the loop end of a treble hook through the thickest liver portion and fold over the extra liver and run the loop though the center of the extra so the liver remains pretty solid and lays around, completely surrounding the hook points. This is the best way to keep it from coming off the hook I've ever found. The fish often suck in and spit out the liver before swallowing but rarely feel the sharp points.
One other tip, you have to use a long, smooth cast to send out the bait. Any sort of "snap" at the start of the cast will pull the hook right through the fragile liver or leave the points exposed.
