In recent years I have been more proactive in being prepared for an emergency or survival situation and for food I looked towards ration packs for a number of reasons.
1. They have a long shelf life.
2. The high calorie content provides sufficient energy.
3. Most are ready to eat and can be eaten cold.
4. The pouches take up less space than canned food.
I prefer the British Army 24 hour ration pack, as it has everything you need for a day in the one box. While with the American MRE’s I like the accessories that come with them but I have found that some menus do not sit so well with me, so I avoid them as the last thing you would need in an emergency or survival situation would be to feel sick because of something you have eaten.
You can get them from some army surplus stores or online at sites like http://www.armyrations.co.uk/, Evaq8 and The Bushcraft Store. You can also find civilian branded meals such like Wayfayer, Look what we found and Mountain House in good outdoor retailers or online.