I have a quart of H2O that hasn't frozen yet in my trunk, in the store bottle. It's kind of wedged between my FAK and jacket in the trunk, with temps in the low teens (and the last week essentially below freezing). If you're really worried, remember that alcohol and salts lower the freezing point. So... either a gin and tonic, or a bottle of gatorade, would probably freeze after a bottle of water.

As for food: 2 3600-cal Mainstay bars, a few power bars, 1 bar of Hershey chocolate, a few small boxes of raisons, some of the Jambalaya "instant" packages, a few foil packets of tuna and spam, and a Esbit stove with 6 tablets. Also have 2 empty quart canteens, 1 of those has a steel/tin? cup with it. Figure I have enough food for a week if I ration well, and a week with 2 people if I REALLY ration well.