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Space Food

Enjoying a meal in space is a very different experience than on earth. Find out what kind of food astronauts eat during their space mission.

BY TOM URBAIN

UPDATED JUN 11, 2024

Every time you’ve gone on a short trip, you might be familiar with this situation: thinking about what kind of food to eat, where to eat it, how to cook it, the kind of resources that would be available, and how to dispose of the waste before returning home.

This basic, familiar process is not that different in space. However, astronauts have limited resources while in space and they need to make the best use of what they have. NASA has to come up with ingenious ways to prepare, stock and store the food that astronauts will consume while aboard the International Space Station (ISS). Like everyone down on Earth, astronauts need wholesome meals and snacks, so their meals include plenty of minerals and vitamins spread across 3000 food choices.

Three astronauts enjoying their space meal in a microgravity environment.

Types of astronaut foods

During the Apollo and Gemini missions, astronauts used to feed themselves by sucking out foods that were stored in tubes (similar to toothpaste tube). Since then, space food has come a long, long way. Today, some of these foods are dehydrated (this is similar to packaged dried noodles we find in stores). To make it edible, all astronauts need to do is add some water inside the package via a syringe.

Few other items are thermostabilized: they are heated to extremely high temperatures and stored in tightly closed containers (like canned soups). Yet other foods are eaten in their natural form (fruits and dried nuts). To store them for a long time, they are sealed in vacuum containers so that there is no air to rot them.

Example of an astronaut healthy meal. On the tray, there are several velcros and magnets to stop the food items from floating away. Source: Wikipedia

Despite the changes in how they eat or store their food, many astronauts have said that eating in space is a fun activity! Living in a microgravity environment for a long period of time psychically affects their bodies. To combat this and keep healthy, they eat three highly nutritious meals and a few snacks each day, as well as doing regular workouts.

A famous space snack developed by the European Space Agency is a muesli bar made with spirulina and goji berries. Spirulina is rich in protein, minerals, vitamins and antioxidants which makes it an important energy source for astronauts on a long mission aboard the ISS.

What do astronauts eat for breakfast?

Astronauts can choose from nine kinds of cereal for their breakfast. Options include Bran Chex, Oatmeal, and Rice Krispies among others. To accompany that they simply need to add a little bit of dried milk and water to the mixture for the meal to be edible.

Astronauts needn’t be deprived of coffee, either. Unlike on Earth, sugar and creamer are already added to the "space" coffee, so astronauts only need to add water and drink it (sugar in its powdered form is very dangerous onboard the ISS, it might enter air vents, astronauts’ eyes and noses, etc).

Being in a weightless environment for a long time affects astronauts bones and results in a loss of calcium over time. That's why their breakfast are nutritionally balanced with calcium-rich foods (milk, yogurt, almonds, etc.) and vitamin D (fish, mushrooms, etc.). Other breakfast items include cinnamon rolls, French toast, pancakes, and apple cinnamon waffles. It all sounds pretty tasty, doesn't it?

What do astronauts eat for lunch and supper?

For their main meals, astronauts can choose from six varieties of soups, including those made with beef, mushroom, and chicken. They can opt for fried or white rice, along with grape juice, fruit cocktails, peaches, and pineapples. As you can see, astronauts may opt for a multicourse meal that’s rich in a variety of nutrients.

Astronauts have recently started to grow their own vegetables, which could help them become more self-sufficient during future missions further out in space (notably the Artemis Lunar Mission). Their little space garden includes lettuce, radishes, mustard greens and pak choi. These vegetables are a great addition to astronauts' lunch and supper for a few reasons: they are highly nutritious, they improve the flavor of their meals and they are fresh, just like the food on Earth, which is thought to have a positive impact on astronauts mental health.

Below is an excerpt from the International Space Station Standard Menu. As you can see, astronauts can choose what they want to eat from a wide variety of food.

How do astronauts clean up after meals?

Astronauts must follow strict hygiene protocols to prevent the growth of bacteria and maintain a clean environment. Astronauts have to clean up after meals just like they would on Earth, but the process is a bit different due to the microgravity environment.

Without gravity, food particles and crumbs can float around and get stuck in equipment, so astronauts have to be extra careful. After meals, they use wet towels and special wipes to clean up any food or liquid spills.

They also use a vacuum system to suction up any crumbs or debris. All waste, including food scraps and packaging, is carefully collected and stored for proper disposal. Maintaining a clean and hygienic environment is essential for the health and safety of everyone on board the ISS, and it requires constant attention and diligence from the crew.

Related article: How do astronauts clean up in space?

Why is astronauts' food freeze-dried?

The Gemini and Apollo programs did not have a refrigerator, and astronauts needed to preserve their food for many months.

In order to greatly increase their shelf life, NASA quick-freezes the foods (quick-freeze is different from usual freezing; it limits the forming of ice crystals in the food, which in turn helps to preserve the taste and nutritional value) and package them up in a vacuum chamber. Doing so deprives the food of its moisture — ensuring that it remains edible for a long time. Freeze-dry foods can be compressed into compact packages that reduce the space required to store them on space shuttles and the ISS.

Space food is delicious. And you can't gain weight. pic.twitter.com/X5BDPAOvdW
— Chris Hadfield (@Cmdr_Hadfield) March 6, 2021

How do astronauts eat their food in space?

Back then, astronauts sucked the food out of tubes (similar to how we squeeze paste out of a toothpaste tube). Now, their eating routines are closer to how we eat on Earth. Of course, astronauts still need to make sure no crumbs floats away when eating their meals.

Their solid foods are broken into pieces before eating so that astronauts can take full bites without leaving a trail of crumbs in their wake. Some foods need to be hydrated with either hot or cold water, so there are tiny tubes aboard the ISS that help astronauts do this. Once they finish eating, they put tiny tablets inside the now-empty food packages to prevent any microorganisms from breeding.

Astronauts seem to enjoy spicy food the most. In 2006, astronaut Thomas Reiter said “Our perception of taste is a little bit decreased. We have a longing for a little bit spicier food.”

Liquids such as coffee, water, and fruit juices are contained in sealed packages made of foil laminate (similar to a Capri Sun). This is because fluids might simply float away if they are squeezed out of the bag too forcefully. So astronauts drink through the straw attached to the container. There are several stations inside the ISS to refill their containers with fresh water.

https://www.youtube.com/watch?v=jYicNMK8PqI

Why food selection is vital for astronauts

One of the biggest challenges in space exploration is providing astronauts with the proper nutrition they need to stay healthy and perform at their best, especially given the physical effects that space can have on the human body. In order to meet the unique needs of space travelers, NASA has developed a specialized system for food formulation and packaging.

This system takes into account the specific nutritional needs of astronauts, including the amount of calories, protein, vitamins, and minerals required to maintain health in the unique conditions of space. Astronauts consume a variety of foods, including pre-packaged meals, snacks, and drinks, all of which are carefully formulated to meet their nutritional needs.

NASA also invests in research to identify new foods and food technologies that could be used to enhance astronaut health and performance during long-duration space missions. It takes about 6 months to travel to Mars from Earth, so it is vital that they find suitable solutions for astronaut nutrition.

The importance of finding sustainable food solutions for long spaceflights

Very recently, an international team of researchers has developed a "space salad" that can meet the nutritional needs of astronauts on long-duration missions. The salad, which is made up of soybeans, poppy seeds, barley, kale, peanuts, sunflower seeds, and sweet potatoes, can be grown in small enclosures on a spacecraft.

The ingredients were chosen for their nutritional value and their ability to be grown with the limited resources and room available on a spacecraft. The team is also working on selectively breeding the plants to increase their nutritional value and decrease their growing space.

As astronauts experience physiological stresses in space, they need nutrient-dense food to offset some of the detrimental health effects of spaceflight. The winning salad was assessed for its psychological value (having to eat the same thing for months can be depressing), with factors like color, taste, texture, and freshness taken into consideration.

The above salad may be part of the dietary plan for astronauts going to Mars in the future. Credit: University of Adelaide

The foods astronauts aren't allowed to eat in space

Bread

Any type of bread has a crumbly texture — a dangerous undertaking for any mission taking place in a microgravity environment. No matter how small the bites the astronauts might take, pieces of bread might escape from the box and float away. Bread is strictly forbidden. The astronauts use tortillas as an alternative to bread.

Alcohol

To date, Buzz Aldrin remains the only astronaut who has consumed alcohol in space (he consumed it when he was in Eagle). NASA later forbid its astronauts from carrying and consuming alcohol during their missions. Alcohol impairs judgment and alertness, and astronauts need both to perform their duties to the best of their ability at all times and especially in the event of an emergency.

Salt, pepper, and other powdered ingredients

Unfortunately for our dear space explorers, they can not sprinkle salt and pepper onto their meals. Just like bread crumbs, it would be an impossible mission to ensure some would not float away and enter air vents, never to be seen again. Astronauts instead use salt and pepper as a liquid that they squeeze out of tubes.

Soda and other carbonated drinks

Sounds like astronauts are missing a lot while in space, aren’t they? Added to the list of things they cannot consume are carbonated drinks. On Earth, the carbon dioxide bubbles separate from the soda and release toward the top of the soda can (called the soda pop). In space, this does not happen, which means the carbon dioxide bubbles stay within the soda because of microgravity. This is not good for astronauts’ health since it will cause a lot of discomforts, which is why they aren’t allowed in space.

Astronaut ice cream

You may have heard of the infamous Neapolitan astronaut icecream. Well... there is actually no evidence that astronauts actually ate ice cream while in space! While the ice cream was certainly designed and developed for the Apollo 7 mission, no one as ever confirmed that the three astronauts had it onboard their spacecraft during their spaceflight to the moon. Ice cream, when quick-frozen, is crumbly in nature and thus a dangerous delight to be consumed aboard the international space station. However, variations of this ice cream are sold in gift shops across the world, mostly in museums.

Fun facts about space food

#1: Expedition 53 crew had a pizza party where they put together a full pizza — in space

On a pizza night in 2017, Sergey Ryazanskiy, Randy Bresnik and Paolo Nespoli assembled a pizza in space, complete with sauces and toppings. You can watch the video here.

Although pizza and movie nights happen occasionally, astronauts do not prefer to take pre-cooked pizzas into space because the crust becomes soft and soggy — that’s definitely not how a pizza is meant to be enjoyed.

#2: Astronauts can eat cakes in space

Their options are Angel food cake, chocolate brownie, chocolate fudge, shortcake, and yellow cake with chocolate frosting. Not bad, right?

#3: First food in space was pureed meat and chocolate sauce

Yuri Gagarin, the first human to fly into space, had two servings of pureed meat and some chocolate sauce during his mission.

#5: Astronauts select their meals 8-9 months before launch

Astronauts can try the food beforehand, offer recommendations and select which ones they’d like to have onboard the ISS for their mission. Their "menus" are then reviewed by scientists in order to calculate the nutritional intake and some adjustments are made in order to ensure that the astronauts are having balanced meals. In space, astronauts can prepare their meals as quickly as 5 minutes.

Fascinating, isn’t it? Given a chance, would you try space food?

Additional Resources:

Try this DIY recipe to make your own astronaut pudding.
Buy some freeze-dried astronaut food from amazon (aff link)
Learn about the "Deep Space Food Challenge". This collaboration between NASA and the Canadian Space Agency (CSA) aims to create new food systems that can fulfil long-duration spaceflight requirements.
Watch this video: Former NASA Astronaut Explains How Food Is Different in Space
Read the "The Astronaut's Cookbook: Tales, Recipes, and More". (aff link) Written by NASA space food scientist Charles T. Bourland.

Frequently Asked Questions

What kind of food do astronauts eat?

Astronauts can choose what they would like to eat during their mission from a menu that has a large selection of food items: cereals, chicken, soups, fish, fruits, eggs, cheese and even cakes!

How long does food last in space?

Space food is either freeze-dried or thermostabilized in order to achieve the required shelf-life which is between 6 to 18 months for space shuttles and the ISS.

Where do astronauts store their food?

Most of the food that is consumed onboard the ISS is stored at room temperature in locker trays. In 2020, 2 space-rated refrigerators were installed on the ISS, allowing astronauts to store fresh food from Earth.