>>10062571: Make an evaporation cooler using wet towels/cloth. Just wrapping the bottle in a wet rag will help cool it.
2: On clear sky nights you can make a chiller using a Mylar emergency blanket, clear plastic, and some sticks. You spread the Mylar blanket out on the ground then tie up the corners to sticks like you are making a hammock. Place the item you want chilled in the center. It should look like a funnel then. Place the clear plastic over they item like a window. Do this under open cloudless sky, without trees above. The clear view of space will actually pull the heat out of the item while the Mylar blanket will block ambient heat from the ground and surrounding things. The clear plastic will slow this down, but prevent warm air from having an effect. You can actually make ice doing this, but it will depend on weather and starting temperatures. It is called a "radiant refrigerator". I did it every clear night to make ice using my solar box cooker.
