How is food prepared in space?

Astronaut Peggy Whitson, flight engineer (left) and Cosmonaut Valery Korzun, commander (right), eating a meal on board the ISS August 2007

The environment of space, and particularly its lack of Earth-like gravity, provides its own peculiar set of challenges and hazards for any otherwise-normal terrestrial activity. Cooking and eating in space is no exception. Whether it’s catering for the effect that microgravity has on human taste buds or stopping any stray crumbs from shorting out sensitive electronics, space agencies have evolved culinary techniques and protocols over the decades, with a little help from the astronauts.

Space food has certainly come a long way since Yuri Gagarin squeezed meat paste from a tube into his mouth on mankind’s debut space flight in 1961. While nutritional appropriateness, ergonomics, weight, shelf-life and practicality for eating in a zero-gravity environment are prioritised, how appetising food is to the crew of the ISS is also an important part of every space agency’s food-research programme. In general, any food taken aboard the ISS should excel in all of these criteria, as well as being quick and easy to serve, simple to clean up and leave little waste behind.

Astronauts have long reported that food tastes different in microgravity and it’s suspected that this has something to do with weight shifting to the upper body and the head. Here, fluids that would normally pool in the lower limbs in Earth gravity disperse more evenly, causing tissues in the face and upper body to swell slightly. This can result in nasal congestion and a decrease in the perception of flavour, making many foodstuffs taste blander than usual to the palate of the average astronaut. This is why ISS crews often crave spicy sauces and strong flavours to liven up their mealtimes.

‘Cooking’ is a somewhat euphemistic way of describing how the ISS crew prepares its meals. Much of the food can be eaten straight from their packets and all the drinks are dehydrated. Coffee, tea, milk and juices are rehydrated using a valve attached to the station in the ISS Service Module, while a similar process is employed for rehydrating the soups, pastas and other dried meals. Despite culinary limitations and regulations, astronauts are free to combines foodstuffs to their heart’s content. Expedition 18 ‘Iron Chef’ Sandy Magnus was notable in her creative combination of everyday ISS food items to form tasty dishes. For example rehydrated rice, chicken, olives, sundried tomatoes, cheese, garlic, onions and pesto came together to form a tasty Mediterranean dish for her ISS ‘Italian night’. Her talents with their limited ingredients also enabled her to cater for the crew around Christmas time. She proved that having a good cook on board can make a huge difference to morale.

Three members of the first manned Skylab mission dine on specially prepared Skylab space food

Space food falls into basic categories that include food thermostabilised with heat to destroy microorganisms that may cause it to spoil, dehydrated foods to reduce volume and the survival rate of microorganisms, natural form foods such as nuts that are already stable, and beverages. This doesn’t include beer or carbonised drinks, because without gravity the gas and liquid in fizzy drinks is unable to separate in the stomach, resulting in a nasty ‘wet’ burp that is distinctly unpleasant in the ISS environment!

The development of food fit for space goes beyond feeding astronauts and keeping morale high aboard the ISS. The Advanced Food Technology Project is NASA’s programme for researching foods with much longer shelf lives than those required aboard the ISS, for missions lasting several years where a resupply from Earth is impossible. A future manned mission to Mars and beyond will require low-mass, high-quality and longer shelf-life foodstuffs. Part of a long-mission duration astronaut’s diet will also be harvested from plants in a hydroponics bay aboard the spacecraft. While food research and technologies for space exploration are far more sophisticated today, the basic challenges of feeding the crew on a year-long mission to a distant world are pretty much the same as those faced by Christopher Columbus, over 500 years ago.

Image Credit: NASA