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Logistics have always been a critical field in any military, more specifically, food logistics. A soldier out on the battlefield, miles away from the nearest kitchen, can be equipped with the most high tech weaponry and gear, but still be almost useless if he is not well fed.
Combat food rationing is probably one of the oldest issues in warfare. Soldiers need food that is lightweight, nutritious, and can last a long time without refrigeration, having the food taste good as well is just a bonus. At the United States Army Natick Soldier Systems Center food engineers are working to do just that.
At the Natick Army base military scientists develop food systems for the armed forces and NASA. The food systems being developed aren’t just new recipes, scientists work to develop efficient techniques to preserve food and cut weight from the food while keeping it nutritious.
Since the 1940s, a popular method of creating combat ready meals was to freeze dry food. Freeze drying takes about two days and allows the food to become smaller and lighter while still maintaining its nutritional value.
However now, a common method used to preserve food for the military is a technique called vacuum-microwave drying. This technique works by placing the food on a rotating tray, which is then placed inside a machine that creates a vacuum. The vacuum lowers the boiling point of water to 20 degrees celsius, compared to 100 degrees normally, which means the food placed in the machine can be microwaved at very low temperatures. After about an hour, half of the water in the food would have been vaporized, causing the food to weigh about half as much as it did an hour ago. The food can then be eaten as is or rehydrated with water.
After the vacuum-microwave drying stage, it is possible to shrink the food even more using a technique called sonic agglomeration. The vacuum-microwave dried food can be placed in an ultrasonic welder where it is then pressed using high pressure and sonic vibrations into a tiny, nutritious disc of food.
Popularmechanics.com reports that the Natick crew has been experimenting with different ways to condense nutrients in those food discs for better preservation.
While it’s easy today to take our access to food for granted, for many soldiers out in the field and astronauts up in space, food is a luxury granted to them due to the efforts of scientists such as the food engineers at Natick.