If you want milk on your next travel trip, try taking a shelf-life or shelf-stable type produce. I’ve froze half pints of Parmalat milk which comes packaged like juice box drinks. This type of milk package, unopened, has a long un-refrigerated shelf life and is good for camping and backup food supplies where weight isn’t an issue. Because it is real milk, it tastes better than powered and the kids like it. Freezing the milk conserves on ice. I did this on a canoe trip and 24 hours after leaving home it was still ice cold and partially frozen.