I'd go with dry foodstuffs and prepared meals. Rice, pasta, beans are good staples. Salt, pepper, spices and dried herbs will spruce up the most mundane things. Nuts and dried fruits are good to have if you like them.
When you reach the "last store" between more remote areas buy alittle fresh fruit, vegetables, meat, fish, eggs, milk etc and pack it in one of those foam coolers with ice. Meat, fish, dairy low down - fruit, veg and eggs in upper portion. Insulate the outside of the cooler with other items - or better yet place this cooler inside a larger one - and the contents should be good for a day or so even if the weather is hot.
