Holiday with Ice

When traveling, we always carry cold drinks in a large thermos for quick refreshment. We used to have a problem keeping the drinks really cold. We tried adding ice cubes, but these would melt and dilute the drink. So now we put ice cubes in a sealed cooking bag and place that in the drink. It not only keeps the drink cold without diluting it, but even when the ice does eventually melt it can be frozen again inside the bag and reused. Charlotte Mitchell, Murray, Utah