I have heard saw dust as well. I myself think it would be too messy in the foodpack. ;D However our group has gotten better at how we keep thing cool. We used to just layer it in tin foil. However this year we layered it in both newspaper, and the tin foil. For the long drive up we keep it in a cooler with a lot of ice. The meat was still frozen when we unwarped it3 days since it was last in a freezer.

I belive sawdust was originaly used back in the days when people used ice boxes to keep food cold. The only way they could keep the ice from melting in summer was to put it under sawdust.