Freeze dried food is good for hikers because it is compact, lightweight and mostly tasty.

So how is it made? Well you take the food and you freeze it. Then you heat it, so rapidly, that the water in the food turns directly into a gas. Then you vacuum pack the food removing the gas. The hiker then adds hot or cold water to the food and eats it.

If you go hiking you are burning much more energy than sitting in your cubicle, so you need more energy in your food. You need to look at the high carb foods, like the pastas, rice or potatoes. If you pick high protein foods you will get tapped out quickly.