Platypus makes a collapsing plastic water bladder that is designed for wine and can be reused. Called the Platypus PlatyPreserve Wine Preservation System, this is a fancy word for a collapsing water bag that is made for wine! At $10 a pop, the price is hefty but if you buy the 4-pack, you save $10.
The bag has a Food-Grade Polyethylene liner and holds 27 ounces but all I care about is that I can pour one bottle of my favorite wine into the thing, squeeze out the air and freeze it with no problem. PLUS, when the wine is gone, I can use my water-filter to fill it with drinking water or simply flatten the bag and it takes no weight or room in my pack or boat. I've used this on a number of trips and never had any problems.
