You are doing a great job collecting all sorts of foods for your doomsday storage, but you have always been concerned just how long it will all last. Your plan is to keep your family fed, not make them sick. I have done some research and have found the answers for you. I hope this helps.
Canned FoodsAs you probably suspected, best by dates don't mean much. These dates are voluntarily placed on products to give a general guideline for how long it will be at its best quality. After this date, you will see loss of color, flavor, etc. Most manufacturers will back their products 2-3 years (depending on the product) after canning which gives you some time at the very least. Some people will insist that canned foods are more likely to last 15-20 years. In 1938, some canned foods were found from an 1820 expedition to the north pole. The cans were 118 years old and the cat who ate the canned meat didn't complain and suffered no ill effects.
Recommendations for some common foods that I have found are; canned meats (2-5 years or the expiration date on the can), baby food (1 year or the expiration date on the can), tomato sauce (1 year), canned fruits (2-5 years), fruit juice (6 months to a year), canned vegetables and baked beans (1-2 years), spaghetti sauce and soups (1 year or the expiration date).
Home canned foods should be find for one year if they are stored in a dry cool place. If they are kept in a warm place or near indirect sunlight, they might lose some of their quality, flavor, or color. If they are in a damp area, the lids may corrode and the food will spoil. Also, make sure that the canning process was followed.
Botulism is also a danger for canned foods, especially home canned foods or rusty cans. It is a potentially life threatening bacteria but can be killed by boiling the food for 10-20 minutes.
Dried FoodsBeef Jerky and dried fruits can last around a year if they are in their original packaging. If you made them yourself, make sure they are properly dehydrated and placed into vacuum sealed bags. Vacuum sealed jerky and fruits should last around a year. If you are just keeping them in a zipper bag or something like that, probably not much more than 15 days. Freezing will make them last longer.
MREAn MRE typically lasts 5 years. Storage temperature is important for an MRE. The lower the temperature, the longer it will last. In temperatures at or below 60 degrees Fahrenheit (15 degrees Celsius), an MRE can last up to 10 years. At a temperature of around 120 degrees Fahrenheit (50 degrees Celsius), an MRE will only last 1 month. An MRE will lose quality and shelf life if stored improperly. Probably not a good thing to keep in the bug-out-bag that you keep in your car all summer.
Freeze Dried FoodFreeze dried foods have the advantage of having very little water or air in them to cause spoilage. The freeze drying process typically removes most of the moisture from the food and oxygen from the packaging. Unopened Cans of freeze dried foods should last around 25 years and pouches last around 7 years. Freeze dried foods can last between 1-2 years after opening as long as minimal oxygen and moisture is introduced into the package. make sure they are kept in an air tight container after opening.
The times suggested in this article are just guidelines for your food storage plan. It assumes that these packaged foods are kept in a dry, cool place, out of the sun, and are kept free of damage. As a general practice, you should throw it away is it smells, looks, or tastes bad.