This may seem to be a simple approach but here it goes. 2 options:
2 separate coolers, one for beers one for food. If you don't open the food cooler till the morning the cooling will last much longer.
The easier option: place your beers in the freezer as well not long enough for them to freeze but maybe 5 hours they would drop to -4 > -7 degrees, but not freeze. Therefore bottles or cans are not damaged but cold enough that they will double the life of your cooler as they will continue to cool all the time they are in there.
