Educator Features

Fresh Ideas for Space Food
04.29.04
Astronaut Peggy Whitson showing a plant experiment in space
"If we go to Mars, we need a garden!" That was International Space Station (ISS) Science Officer Peggy Whitson's first thought after one of her crewmates joked about making a salad with soybean plants they had grown as part of an experiment. At the time, it was the only thing even close to fresh fruit or vegetables the crew had left after weeks in orbit.

Image to right: Astronaut Peggy Whitson holds plants from an experiment on the International Space Station
Credit: NASA


"Space food" has come a long way during the 40 years man has been flying in space. In the early days, astronauts ate food that came in dried cubes or had to be squeezed out of a metal tube. Today, they have a wide variety of options and their meals are much closer to those found on Earth. However, with the arrival of the International Space Station, space cuisine took a small step backwards for ISS crew members.

One thing that is missing on the Space Shuttle and ISS is a refrigerator. This means that fruits and vegetables can only be kept for short periods of time. For astronauts on the Space Shuttle, this creates a few limitations on what foods they can bring. But for Space Station crew members, who spend months in orbit, it creates a bigger problem. Since their missions last much longer, they can go long periods of time without eating any fresh produce.

Fresh fruits and vegetables are loaded onto the Space Shuttle less than 24 hours before launch. They are kept in a special fresh food locker. Tortillas, fresh bread, and breakfast rolls are also included.

During spaceflight, fresh fruits and vegetables have a short shelf life. They must be eaten within the first week of flight. Carrots and celery sticks are the most perishable items in the fresh food locker. They must be eaten within the first 2 days of flight. This is because the locker they are stored in is not only unrefrigerated, but is also located near electrical equipment. The equipment raises the temperature in the trays to around 29 to 32 degrees Celsius (85 to 90 degrees Fahrenheit). This extra heat quickens the spoilage of the fresh food stored in the locker.

Picture of astronauts in space with oranges floating in front of them
Image to left: Fresh fruit is not always available while living in space
Credit: NASA


Crew members on the International Space Station do not have to go without fresh fruits and vegetables for their whole trip. New supplies of fresh food are brought to the Station either by the Space Shuttle or by the unmanned Russian Progress supply ship. These are one of the most prized deliveries for astronauts. Astronaut Whitson said that when a Progress supply ship arrived after she had been in orbit for months, "Fresh fruit and tomatoes seemed like a fantasy... Tomatoes have never tasted so succulent and apples so sweet!"

Astronaut Dan Bursch, who spent 6.5 months on ISS, agreed. "Getting fresh fruit on board was great," he said. Bursch said that he missed not only the taste of fresh fruit, he missed the smells of plants, and occasionally opened the plant-growth experiment because "I just had to take a few whiffs of the plants." He said he also enjoyed the smell of fresh fruit when it was brought to the Station. "But after about 3 weeks, the fruit didn't smell so good, and we had to get rid of it."

Even when fresh fruits and vegetables are not available on the Space Shuttle or Space Station, astronauts have them available in other forms. Things like applesauce, fruit cocktail, dried fruits, peanuts, and fruit juices have a much longer shelf life. They will last throughout a long Space Station stay.

In the future, fresh fruits and vegetables for long-term spaceflights may be provided the old fashioned way. Today, NASA prepares food for the Space Shuttle and Space Station like a family prepares for a picnic. All of the food is readied and packed before the trip. On a manned spaceflight beyond Earth's orbit or at a long-term space colony in the future, packing enough food might not be realistic.

To avoid packing lots of bulky food, astronauts could grow their own. Scientists must study different types of crops to decide which would be best suited for space travel. Those with a short life cycle, such as lettuce, could be grown in space and provide diversity in crew menus. It could even be used on the ISS. Growing plants on a spacecraft or space colony would provide other benefits as well, helping to maintain the environment by giving off oxygen.

Many things must be considered before we can begin farming in space. NASA is researching ways to make growing crops easier and more practical. Different kinds of lights are being studied as a way to replace the plants need for the Sun. Alternatives to traditional hydroponics, such as growing plants in water-soaked cloths, are being considered. These techniques will eliminate the need for heavy soil. In addition to paving the way for new methods of dealing with fruits and vegetables in space, this research has led to improvements on Earth as well.

Picture of oranges that were kept fresh using NASA technology
A device that NASA hopes will eventually help keep food fresh longer in space is currently being used to keep food fresh longer on Earth. The same research even led to an invention that can be used to kill anthrax. Anthrax is a bacterium that can be deadly to humans if inhaled. Unfortunately, it has been used in bioterrorism (for more information about this device, visit http://commercial.hq.nasa.gov/files/release02-50.html). Who would have thought that work done to help astronauts have fresh fruits and vegetables could be used in the war against terrorism?

Image to right: NASA is experimenting with ways to grow and keep plants and fruits fresh in space
Credit: NASA


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Published by NASAexplores