Dehydrated foods are the survival food of the 20th century. The choice of backpackers for it’s light-weight and low volume, it’s long term shelf life and the ability to create pre-prepared entrees with multiple ingredients including meats, vegetables and dairy, dehydrated packaged foods were the rage.
Dehydration could have been talked about along with drying and desiccation but it’s kind of held to a certain standard these days. Drying is anything drier than the food was at harvest. Food which has been dehydrated is held to be at very low moisture levels. We manage to preserve higher nutritional values in food desiccation stored for the long term with dehydration than with other methods. It is possible to dehydrate food on your own using solar, fire or other heat source but in some areas, the ambient humidity is just working against you every step of the way. From handling food in atmosphere to the containers you put it into, some places are just too dang soggy. That could present some challenges.
Dehydrated foods offer many advantages. We can have almost anything in dehydrated food: eggs, cheese, juices, meat, prepared entrees, any kind of plant crops, they just have to be “rehydrated” for use after storage. However, it’s important to note that most dehydrated long term storage foods are packaged as “single-foods”. In other words you will likely be buying large packages or cans of peas and that’s all there is in there. It’s generally not pre-packaged entrees like we get with a lot of freeze dried survival foods. Ultimately a well planned store of dehydrated foods such as are found in the commercial packages offers more options for long term sustenance. Dehydrated food is also cheaper, it’s about the cheapest (or low-cost, rather) food you can get. I generally favor dehydrated and dried foods for long term storage for all of these reasons.