Buy dry foods, canned goods and peanut butter, then use the oldest on a regular basis and rotate new stock into the pantry. Too many people buy foods that they will only eat when the SHTF and then since you’re not using it on a regular basis, it’s gone or going bad. If however you buy many of the foods you currently eat for SHTF planning then you can eat the oldest food and rotate new stock into your holdings as a routine part of your meals.
Freeze-dried food is nothing new. As early as the 13th century, the ancient Quechua and Aymara people of Bolivia and Peru pioneered a form of the process by exposing potatoes to the freezing temperatures of the Andes overnight, then drying them in the sun. In 1937, Nestlé used industrial technology to create the world’s first freeze-dried coffee, and in the 60s and 70s, the US military shipped freeze-dried food rations to the troops in Vietnam.