Pea soup has been, and still is, commonly used food in the Finnish military for several good reasons: a) it has excellent nutritional value, b) the main ingredient, dry beans, is very light weight, and has a very long storage life, c) the soup itself is easy to prepare for a large group of people, and d) in practice, it cannot be over cooked, and it can be reheated for several times.
Pea soup is also a very good dish for any campers, hikers or survivalists, who wish to enjoy tasty and nutritious hot meal every now and then. However, the soup has some unpleasant properties. One, preparing the soup from scratch, ie. from dry beans, takes a good 16 hours (at least 12 hours to soak the beans, and few hours of cooking), two, home made soup does not stay good for a very long time, and canned soup does not taste good to begin with, and three, as all of the soups, also the bean soup, even concentrated canned pea soup, contain lots of water, and is a bitch to carry around.
Fortunately, to circumvent these problems, it is possible, and very easy too, to dehydrate the soup.
Dehydrated pea soup, even with some meat in it, stays good for weeks in a backpack, and the weight reduction in comparison to the wet soup is about 80%, and best of all, preparation of delicious pea soup from dehydrated ingredients at a camp site is as easy as it can get.
Due to the facts that soup spills easily, and that a large flat area speeds up the evaporation, for dehydrating soups, or any other relatively liquid stuff, a conventional oven is better than a regular food dehydrator.
To begin the process, heat an oven to about 50 C (122 F), and line an oven tray with baking paper. Then spread the soup (either home made or canned) evenly on to the tray. One average size tray can handle anything between 500 and 750 ml (2 to 3 cups) of soup. Place the tray in to the oven and wedge the oven door slightly open with some wooden or metal kitchen utensil. Dehydrate for 14 to 24 hours (depending on the amount and the water content of the soup) till the soup is dry and the consistency brings corn flakes into your mind. Pack the dehydrated soup into a ziplock bag, and store in a cool dry place. If your soup contains meat, I recommend freezing it for long term storage.
To prepare pea soup at a camp site, try to remember what was the original volume of the soup, and heat up equivalent amount of water, and pour it into a pot on top of the dehydrated materials. Then simmer the soup on low heat (use the simmering ring with Trangia burner) for 20 to 40 minutes till the peas, and especially the meat, are rehydrated, tender, and hot. The slowly boiling soup can pretty much be left alone for the whole time, but a little stirring a couple of times during the process is recommended.
When the soup is done, season with some mustard, which, in addition to tasting good, also thickens the soup a little bit, and enjoy.
One full Mini trangia pot of soup contains about:
Energy 2500 kJ
Proteins 35 to 60 grams (depending on the meat content)
Carbohydrates 85 grams
Fat 25 grams