Our only way to keep food cold while traveling is with our Igloo bear-proof cooler (similar to this guy here) that we lash onto our tongue cargo rack. Over the years, we have gone through numerous ways to pack as much food as possible without having our fresh eggs swimming in melted ice water with random bags of lunch meat.
The best solution we have come up with is to use several storage containers from Walmart to hold the food in separate compartments, while the ice surrounds the containers. This keeps the melting ice from soaking the fresh food. The top container holds fruits, veggies and other items that don't need to be very cold, while the bottom container holds meat, dairy and frozen items that tend to keep the cold items colder. The surrounding ice can hold more breakable items like beer or soda bottles.
Since plastic container products and sizes are always changing, the best way to accomplish a similar setup is to bring your ice chest to the store and try to fit several containers into it. We were able to find a set of containers with handles that nested into each other. When we want to do some cooking, we will just pull out the container and carry it to the stove and our picnic table.
