Stability of Nutritional Compounds (Stability-Nutrition) - 08.29.18

Overview | Description | Applications | Operations | Results | Publications | Imagery

ISS Science for Everyone

Science Objectives for Everyone
Stability of Nutritional Compounds (Stability-Nutrition) studies the effects of the space flight environment, including radiation, on complex organic molecules, such as vitamins and other compounds in food. This helps researchers develop more stable and reliable foods and packaging materials, and nutritional countermeasures, suitable for future long-duration missions beyond low Earth orbit.
Science Results for Everyone
When food goes bad in space, you can't run to the corner store for more. Good nutrition is critical on missions. Stability-Nutrition studies the effects of space flight on food in hopes of finding more stable and reliable foods and better packaging materials for long missions. Researchers are finding out that nutrient degradation rates were similar between food in flight and on the grounds, indicating that storage had more of an effect than being in space. Exposure to low Earth orbit radiation has little effect on nutrient quantities. These results will help NASA design food packaging and preservation for both ISS and long-term space exploration missions.

The following content was provided by Scott M. Smith, Ph.D., Sara R. Zwart, Ph.D., and is maintained in a database by the ISS Program Science Office.
Experiment Details


Principal Investigator(s)
Scott M. Smith, Ph.D., NASA Johnson Space Center, Houston, TX, United States
Sara R. Zwart, Ph.D., University of Texas Medical Branch, Houston, TX, United States

Vickie A. Kloeris, M.S., NASA Johnson Space Center, Houston, TX, United States
Michele H. Perchonok, Ph.D., NASA Johnson Space Center, Houston, TX, United States
Leslie A. Braby, Ph.D., Texas A&M University, College Station, TX, United States

NASA Johnson Space Center, Human Research Program, Houston, TX, United States

Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)

Sponsoring Organization
Human Exploration and Operations Mission Directorate (HEOMD)

Research Benefits
Information Pending

ISS Expedition Duration
April 2006 - April 2009

Expeditions Assigned

Previous Missions
Stability-Nutrition is a unique investigation that was begun during ISS Expedition 13.

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Experiment Description

Research Overview

  • This investigation evaluates whether vitamins and amino acids degrade in space by collecting data on the select foods flown in space for varied lengths of time.

  • The data gathered supports the development of mathematical models to predict shelf life of products for long-duration exploration missions and provide the foundation for future efforts on alternative formulations, packaging and shielding materials for foods to ensure integrity and quality of products used by crew during exploration missions.

Degradation of food products during space flight may render them ineffective in providing nutrients and energy. The stability of foods used by the crew must be adequate to facilitate safe exploration of space in the future. The Stability of Nutritional Compounds (Stability-Nutrition) investigation evaluates mission critical medications and foods to understand issues relating to nutritional adequacy of foods in space.

Nutrients are vital for every cellular process in the body, both on Earth and in space. It is evident that the status of certain vitamins in the body is altered during long-duration space missions, but it is not known if vitamin metabolism is altered, if the vitamins in the food supply have been degraded, or if the food supply contains enough of each nutrient throughout the mission. For example, other studies have shown that folate status is decreased after 3- to 4-month missions. It is possible that high levels of ionizing radiation or long-term storage could destroy nutrients in foods or decrease their bioavailability. Either of these would lead to impaired nutritional status in crews consuming these foods.

Stablity-Nutrition results from nutritional products could provide important information about the susceptibility of vitamins, amino acids and fatty acids in the space food system to adverse environmental factors encountered during space missions. These results will assist in determining if modified requirements are necessary to avoid malnutrition in crewmembers. The results will also indicate whether improved packaging designs will be needed to protect food from irradiation and long-term storage conditions during long duration space exploration missions. This data will be useful in identifying alternate methods of preparation and storage of these specific food systems to minimize loss of nutritional value during long-duration space exploration missions.

Four identical Stability kits were delivered to the ISS in July 2006 during the STS-121/ULF1.1 mission. The first kit was returned to Earth during the STS-121/ULF1.1 mission. The second kit was returned after 11 months of exposure during the STS-117/13A mission in June 2007. The third kit was returned after 1 year and 7 months of exposure during the STS-122/1E mission in February 2008. The fourth kit was returned on STS-128/ULF2 in November 2008.

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Space Applications
Results of this investigation will provide important information on the susceptibility of select foods and vitamins to adverse environmental factors encountered during space missions.

Earth Applications
The results of this investigation will help understand the effects of adverse environments on food, this information will assist Earth based explorers in making healthy choices for long-term exploration of remote and adverse habitats like the Antarctic.

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Operational Requirements and Protocols
Each kit consists of 7 food items that include vitamin supplements, a passive dosimeter and a temperature monitor. Each kit will be stored for different periods of time to gather time course data on radiation and temperature conditions on board. All sample kits flew to ISS on STS-121/ULF1.1 in July 2006. Kit 1 was returned on STS-121/ULF1.1 in July 2006; Kit 2 was returned on STS-117/13A in June 2007; Kit 3 will return on STS-122/1E in February 2008; Kit four will be returned on a future flight. Storage requirements for all three kits are that they must be stowed together on ISS, the location in relation to on-board radiation monitors must be identified, and they should not be stowed next to a heat source.
Stability-Nutrition is a passive investigation that will require minimal crew time while on orbit. The crew will transfer the sample kits from Shuttle to ISS; then back to Shuttle at the appropriate time intervals. Following return to Earth the samples will undergo a battery of physical and chemical evaluations to determine shelf-life and degradation profiles of vitamin and amino acid contents in food preparations.

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Decadal Survey Recommendations

Information Pending

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Results/More Information

Items examined were tortillas, salmon, almonds, broccoli au gratin, dried apricots, a multivitamin, and vitamin D supplements. In general, the study found that, while there were differences between the vitamin concentrations of food flight samples and ground samples, the degradation rates of nutrients were comparable in both sets. These results made it clear that long duration storage had a considerably larger impact on nutrient stability than flight in space. Prominent changes as a result of storage included the approximate 50% decrease of both folic acid and thiamin in tortillas, 15% to 20% decrease of folic acid and vitamins K and C in broccoli au gratin, 10% to 35% decrease of riboflavin and vitamins A and C in the multivitamin, and a 200% increase of hexanal, which indicates that an increase in lipid peroxidation (and flavor) occurred in almonds. Exposure to low Earth orbit radiation had no effect on nutrient quantities. The results from this study will aid in the design of future food packaging and preservation systems for both ISS and long-term space exploration missions (Zwart et al. 2009).

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Results Publications

    Smith SM, Heer MA, Wang Z, Huntoon , Zwart SR.  Long-duration space flight and bed rest effects on testosterone and other steroids. Journal of Clinical Endocrinology and Metabolism. 2012 January; 97(1): 270-278. DOI: 10.1210/jc.2011-2233. PMID: 22049169.

    Zwart SR, Kloeris VA, Perchonok MH, Braby LA, Smith SM.  Assessment of Nutrient Stability in Foods from the Space Food System After Long-Duration Spaceflight on the ISS. Journal of Food Science. 2009; 74(7). DOI: 10.1111/j.1750-3841.2009.01265.x.

    Zwart SR, Morgan JL, Smith SM.  Iron status and its relations with oxidative damage and bone loss during long-duration space flight on the International Space Station. American Journal of Clinical Nutrition. 2013 May 29; epub. DOI: 10.3945/ajcn.112.056465. PMID: 23719548.

    Zwart SR, Gibson CR, Mader TH, Ericson K, Ploutz-Snyder RJ, Heer MA, Smith SM.  Vision Changes After Spaceflight Are Related to Alterations in Folate- and Vitamin B-12-Dependent One-Carbon Metabolism. Journal of Nutrition. 2012 Mar 1; 142(3): 427-431. DOI: 10.3945/jn.111.154245. PMID: 22298570.

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Ground Based Results Publications

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ISS Patents

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Related Publications

    Smith SM, Zwart SR, Block G, Rice BL, Davis-Street JE.  The nutritional status of astronauts is altered after long-term space flight aboard the International Space Station. Journal of Nutrition. 2005; 135(3): 437-443. PMID: 15735075.

    Smith SM, Zwart SR, Kloeris VA, Heer MA.  Nutritional Biochemistry of Space Flight. Happauge, NY: Advances in Clinical Chemistry; 2008.

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Related Websites

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image Video screen shot of the Stability ground control inside the Orbiter Environment Simulator (OES) chambers at Kennedy Space Center. Inset image is the medical contents of Stability. Four identical Stability payloads were sent to ISS, and returned to Earth at different intervals for analysis of degradation of nutrients.
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image NASA Image: P1010019 - Stability Kit 3 before flight to ISS on STS-121/ULF1.1.
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image Temperature Data Logger and Dosimeter that were placed inside of the Stability kits.
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image NASA Image: ISS009E08874 - NASA ISS Science Officer Mike Fincke smiles at the camera as juggles newly arrived fruit during Expedition 9. Nutrients from fresh fruit periodically delivered to ISS help keep through crew healthy throughout their stay on ISS.
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