There are times when putting a canteen of water in the freezer is desirable for a number of reasons. The general advice is to leave about ten peer cent of the canteen empty to allow for the expansion of ice as it freezes.

This is very good practice for solid plastic or metal canteens, but I have wondered about cheaper containers, notable recycled sports drink (Gatorade) bottles. I have long wondered if the various furrows and grooves in these bottles would allow for expansion without breakage.

I have tried on two occasion to freeze fully loaded Gatorade bottles in the freezer and it works! No breakage, just expansion. I imagine there would be similar results with other brands of sports beverages, as long as the containers are not smooth.

Ten per cent additional capacity isn't much, but I have seen cases where the extra bit of cool clear water would have been very welcome....