How do astronauts eat?

Eating in space for John Glenn (the first American to orbit the Earth) turned out to be an easy though not too tasty experience. Before the flight, some experts were worried that, in weightlessness food would be hard to swallow and as a result, collect in the throat. Glenn found that eating in space was relatively easy and once the food reached the mouth, there was no problem in swallowing.

Other Mercury astronauts following John Glenn were forced to endure bite-sized cubes, freeze dried foods, and semi-liquids in aluminum toothpaste-type tubes. They found the food unappetizing, had trouble rehydrating the freeze-dried foods, and disliked squeezing the tubes. Futhermore, crumbs from the bite-sized cubes had to be captured to prevent them from fouling instruments.

In the Gemini missions eating in space became more normal. The aluminum tubes of the Mercury program were replaced because the container weighed more than the food inside. Bite-sized food chucks were coated with an edible gelatin to reduce crumbling.
Rehydratables were encased in an improved plastic container. To rehydrate food, water was injected into the pack through the nozzle of a water gun. After kneading the contents the food became a puree and was squeezed through a tube into the astronaut's mouth.

Further advances in Apollo food systems came with the introduction of the "spoon-bowl" package for rehydratable foods and retort pouches for thermostabilized foods. Following rehydration of the contents in the spoon-bowl, a pressure type, plastic zipper was opened and the food removed with a spoon. The moisture content in the food enabled it to cling to the spoon, making eating a more normal experience.

In the Space Shuttle ... Food needing rehydration is given hot or cold water in premeasured amounts. Water for rehydration comes from the Orbiter's fuel cells that produce electricity by combining hydrogen and oxygen gas. Since water is a useable biproduct from the fuel cells, much weight can be saved by sending up food in a dried form for rehydration in space. To simplify food packaging a new rehydratable food pack design is used. The bottom of the package is an injection-molded, high density polyethylene base. A thermoformed flexible lid made of plastic film covers the top. To add water, a large gauge hollow needle is inserted through a septum in the base.

Food needing heating is placed in a forced air convection oven, a new feature for space flight. The maximum temperature of the oven is 82°C (180°F) and it can hold temperatures at 65°C (150°F) for an extended period. The oven can heat containers of different sizes and shapes.

Beverage containers for the Shuttle are identical to the packages for rehydratables. A polyethylene straw is inserted through the same septum that is used for injecting water. When not in use, a clamp closes the straw.

While the astronauts are eating, food containers are held in a food tray that is attached to a table in mid-deck, to the astronaut's lap while seated, or attached to a wall. Eating utensils consist of a knife, fork, spoon, and a pair of scissors for cutting open packages. Food can be seasoned with serving-sized packets of mustard, catsup, mayonnaise, hot sauce, and liquified salt and pepper. Following the meal, food containers are discarded and the utensils and serving trays are cleaned with "wet wipes."

"George Files" by Parenting the Next Generation