The thirty day ration pack is intended as a way of surviving economic hardship or a disruption to local food supplies (flood, general strike, adverse weather ext). It is the base upon which more advanced systems may be built.
Food and drink
8 cans of baked beans (cheap source of protean and energy)
8 cans of chopped tomatoes (can make a meal out kitchen scraps)
8 cans of kidney beans (very cheap)
8 cans of peas
8 cans of tinned fruit (good source of liquid)
8 cans of chunky soup
8 cans of corned beef
8 cans of vegetables
All of these items may be eaten cold if needed.