The latest NASA food safety spinoff is all about purifying the air around the food to make it safer. The 1995 space shuttle Columbia mission included an experiment to demonstrate how food could be grown in greenhouses by astronaut pioneers on the moon. This experiment consisted of a small greenhouse fitted with a special device to reduce the amount of ethylene buildup. Comprising carbon and hydrogen, this gas is produced naturally by plants and helps them ripen. In the sealed environment of a space greenhouse, ethylene gas can build up, making food plants ripen too quickly and begin to spoil.
In order to increase the lifespan of crops grown in space, the ethylene has to be removed. NASA invented a device called an ethylene scrubber, which circulates the greenhouse air through tubes coated in titanium dioxide and then exposes it to ultraviolet light. The resulting chemical reaction converts the ethylene gas to water and carbon dioxide -- both of which are good for plants. Aboard the Columbia, the ethylene scrubber successfully preserved a batch of potato seedlings for the duration of the mission.
In 2001, two companies paired up to license this NASA technology for commercial food use under the name AiroCide. Further NASA testing had shown that the scrubber not only removed excess ethylene to kept perishable food fresh longer, it also killed potentially dangerous airborne pathogens such as viruses, mold, bacteria and fungi. KesAir claims that AiroCide even removes bad odors. Many grocery stores, food processing plants, food storage companies and restaurants have installed units to both prevent food from spoiling and reduce the spread of foodborne illnesses.
Refrigerators containing the technology are also available for home use. Unlike traditional air filtration systems, AiroCide units don't use chemicals or create any dangerous byproducts such as ozone.