I don't know what your set up is- cooler, fridge or backpacking- how long yer going out for so I'll just throw out some suggestions as they come to me, LOL.
Backpacking- freeze a small container of milk and only eat cereal as long as the milk lasts. Powdered milk made w/ cold water placed in a shakable container. Forego the milk and substitute yogurt which lasts longer w/o refrigeration.
Cooler- store milk next to a block or two of ice. I make my blocks by freezing liquid filled juice bottles.
Fridge- open and pour:B.
HTH!