• The weightlessness and lack of ventilation prevent astronauts from consuming whatever they want, according to our partner The Conversation.

  • After eliminating those incompatible with space travel, seven types of food remain available.

  • The analysis of this phenomenon was carried out by Yaël Nazé, FNRS astronomer at the Institute of Astrophysics and Geophysics of the University of Liège (Belgium).

It's true that eating in space is no easy task!

First, there is the problem of weightlessness.

Floating unhindered certainly seems very amusing to us, but it is immediately less funny if you have to chase your hamburger strolling through the cockpit ... Indeed, a simple gesture a little abrupt, and here is your meal that s' flies away, the liquids taking on the spherical shape.

In addition, crumbs and droplets of all kinds cause real problems because they can damage equipment or, more seriously, clutter the lungs of astronauts.

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Then there are the usual space restrictions: the heavier it is, the more expensive it is to send up there: thus, sending a kilogram into space costs around 10,000 euros!

We must therefore limit the mass and volume of food packages intended for astronauts… without forgetting to minimize waste!

The waste is stored in the passenger compartment until returning to Earth.

And when we talk about waste to be limited, this obviously concerns all waste: for example, the primitive toilets of the first ships did not make “big commissions” so much easier.

Thus, the proportion of fiber in the spatial menus was intentionally kept as low as possible.

Fortunately, the improvement of the evacuation system quickly put an end to this restriction.

Luca Parmitano, flight engineer, pictured with the food floating in the International Space Station © NASA, CC BY

Finally, there are two specific food issues.

The first is the lack of ventilation - no question of opening a porthole on pain of immediate death!

The confined space of the space cockpits therefore does not allow you to grill your steak (hello smoke ... which turns into persistent fog for the rest of the mission!) Nor to take your favorite Maroilles, even if you are ch ' ti.

Some captains even have a leitmotif: "no banana on board", the harmless smell of this fruit apparently getting on your nerves when you bathe there for several days in a row ... The second problem is the lack of refrigeration.

The food must therefore "hold" at room temperature: all spatial menus therefore undergo strict microbial control before departure.

On the other hand, you can heat food without any problem.

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Seven types of food are available:

  • Fresh food, for example fruits and vegetables to eat in the first days of the mission or supplies.

  • Food known as "in natural form", untreated: for example candy (M & M's are very popular for the variety of games they lend themselves to), nuts, cookies (small enough to be swallowed in a bite, avoiding crumbs), sweets of all kinds.

    There is no conservation problem here: sweets are made to stay in terrestrial distributors for a long time ...

  • Dried foods, also unprocessed: for example dried apricots, dates, beef jerky, which do not require any preparation.

  • Food thermostabilized, that is to say sterilized by heating to prevent the development of microbes.

    Clearly, these are our good old preserves.

Astronaut Sandra Magnus, with food she prepared in the International Space Station kitchen © NASA, CC BY

  • Irradiated foods, for example smoked turkey or smoked sausages, which can be stored for a very long time at room temperature.

    The radiation here helps to kill bacteria, thus increasing the shelf life.

  • Rehydratable food, the preparation of which consists of injecting water (hot or at room temperature) with a syringe.

    This category includes powdered drinks (fruit juice, soups, milk chocolate) but also freeze-dried foods (i.e. frozen and then dehydrated) such as shrimp cocktail and macaroni and cheese.

  • Condiments, for example salt, pepper, ketchup, mayonnaise.

    The first two are entitled to special treatment: they are supplied in liquid form, the salt dissolved in a little water and the pepper suspended in the oil.

    Indeed, one can easily imagine the damage of a cloud of pepper coming to titillate the nose of the astronauts at a crucial moment, type "Houston, we have a problem" ...

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This analysis was written by Yaël Nazé, FNRS astronomer at the Institute of Astrophysics and Geophysics of the University of Liège (Belgium).


The original article was published on The Conversation website.

Declaration of interests

Yaël Nazé does not work, does not advise, does not own shares, does not receive funds from an organization that could benefit from this article, and has not declared any affiliation other than his research organization.

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