keeping ice cream fresh for 12 hours while transporting Is it possible to keep it fresh during a long distance travel by train? Normal styrofoam boxes won't work I guess, what about thermos flasks?
My dad used to buy icecream after a long day work for us (it was a 3 hour drive.) 
He used styrofoam boxes with some dry ice. Not sure if it can hold up till 12 hours.