What do astronauts eat in space?

What do astronauts eat in space? Nutrition is the basis of human health. Among the fifteen disciplines dealt with by NASA, there is nutrition. This discipline is the subject of scientific research because an inadequate nutrition is likely to compromise crew health and mission success. The quality of food consumed in space has improved since the first space missions. Safety in space and keeping astronauts in top condition are a priority which must be met the food on board.

The maintenance of the health of astronauts depends on the contributions of the various nutritive substances. The food problem deserves a very particular attention and brings together logistical problems (storage), sanitary (food preservation), nutritional (covering needs) and, psychosocial (pleasure and conviviality) ones. Respect for the act of eating in its three different functions (biological, psychological and sociological) is essential for the physical but also psychological balance of the crew members.

A good part of social life on Earth is summed up around meals. In the same way in space, the meal must also contribute to the creation of a relational space of relaxation and sharing. To guarantee the cohesion of the team and participate in the psychic balance of the astronauts, they find and share, if not all meals, at least one meal each day. But the way of eating in space is not the same as on Earth.

In the past, space explorers swallowed tube food, chewable tablets, tasteless mash, and cold, dehydrated cube food. But gradually things have improved, from Yuri Gagarin to the first steps on the Moon. Some like the Apollo crews could benefit from the hot water on board. Then, later, the space supply shifted from the tube of unappetizing dough to tasty dishes made by great starred chefs. What do astronauts eat in space? There has been refined meals onboard the MIR station in 1996. The European Space Agency (ESA) works with European chefs to make quality space food. The creation of a full range of tasty, balanced and diet meals was made possible thanks to the partnership between CNES, the French space agency, ESA and ADF (Alain Ducasse Formation). Daily food aboard the International Space Station has American-Russian dominance even if everything is done to avoid blandness and monotony. Exceptional events such as birthdays are celebrated with special dishes.

Between one and two years before the space flight, missioned astronauts are invited to taste most of the dishes, and should assign a note that will allow them to remember what they liked and disliked at the right time and, make their selection a few months before departure. Standard menus are also available. But astronauts have the possibility of substituting a few products to satisfy their own taste and even to compose all of their menus themselves.

Concerning what astronauts eat in space, dietitians have an obligation to evaluate these modified menus in order to examine the nutritional balance with total energy intake and coverage of macronutrient, vitamin and mineral needs. As for health security, dehydration and sterilisation are the two main techniques for preserving food.

The dishes are mainly freeze-dried in those present in these official menus. There can be found, among other things, what is left of heat-stabilized dishes, or dishes precooked in sauce, all having a shelf life of at least two years, and packed in thick aluminium pouches that just need to be put in an oven. On the other hand, there is food ready to be eaten without being cooked or plunged in water: it is the case of cereal bars, cookies, dried fruit, candy and treats.

For safety reasons, an additional quantity of meals is on board, capable of providing each of the crew’s astronauts two thousand calories daily over several days. Food is stored at room temperature. The onboard stock must be reduced to a minimum in volume as well as in weight. For longer stays, a supply vessel moored at the International Space Station (ISS) to refuel it with fuel or food, thereby sending fresh products. ISS astronauts can eat quail, spicy and stir-fried Thai-style chicken, celeriac in delicate nutmeg puree or rice pudding with candied fruit. Meals are stored in large lockers about three weeks before departure and positioned in the order in which they are eaten. Said lockers will only be installed on board two to three days before launch.

The astronauts each have a respective color, which identifies their choices of food and equipment. The front of the locker has a label stating its contents. The crew also has a “fresh food locker” which, unlike in the past, now makes it possible to store food of their choice, which must obviously be checked by the space agency which will issue a health certificate. There are also a variety of drinks, sweet or not, including fruit juices, lemonades, black coffee, café au lait, tea, infusions that are reconstituted by rehydration and drinkable with straw. Alcohol is prohibited except in cases beyond the control.

Space dishes are familiar dishes, and appetizing. Some are prepared quickly in orbit and are a pleasure for astronauts. The rhythm of the meals is respected in the same way as on Earth with a breakfast, a lunch and a dinner with the possibility of snack between two meals. If the astronauts use the straw for liquid food, the fork, the knife and the spoon are used as on Earth. Today, the waste is compacted and stored in a compartment provided for the occasion, then brought back to Earth or burned in the atmosphere.

Trays and utensils are cleaned regularly. The foods are contained in closed packages so as not to disperse in an environment in microgravity because dangerous for the instruments on board and the health of people onboard the ISS. Conservation tests and microbiological analyzes are carried out on the food onboard. Astronauts use meal trays as a plate.

The sense of smell is no longer the same once in space. The flavors are less strong or sometimes transformed. As a result, the dishes must be much salty and spicier to be appreciated up there. Space cuisine is concerned with this so that the orbital meal rightly meets physiological and psychological needs.

Finally, concerning what astronauts eat in space, the case of other celestial bodies is particular. For the food on Mars, it will be a difficulty to feed the astronauts. Therefore, the regular dispatch of supply vessels is not a realistic option. A space farm that will allow the cultivation of the consumed products has been envisaged, while recycling waste and water. Research has been started by the European Space Agency to define what could be cultivated and to study the feasibility of an autonomous ecosystem. These techniques, which would thus be developed for space, could be used on Earth and could have fundamental results in an environment where resources are dwindling and where population is increasing.

This article was written by Mensah Binassoua Yehouessi (Paris-Saclay).