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Carbonated Beverages in Space
Astronauts must give up many of the comforts of home when they embark on space travel -- privacy, the comfort of a familiar bed, home cooked meals, and even carbonated beverages are all left behind on Earth.
The bubbles of carbon dioxide in carbonated beverages aren't buoyant in a weightless environment, so they remain randomly distributed throughout the fluid, even after swallowing. This means that carbonated beverages including soft drinks and beer may become a foamy mess during space travel.
Vickie Kloeris, Subsystem manager for Shuttle and ISS food systems at Johnson Space Center and program manager for NASA FTCSC, says "carbonated drinks currently don't make the trip because the carbonation and the soda will not separate in microgravity. Some experiments have been done with special microgravity dispensers for soda, but it has not been perfected yet."
Even if a microgravity dispenser is perfected, there is no guarantee that carbonated beverages will be used in space. In space, with the absence of gravity, the carbon dioxide bubbles in carbonated beverages go through an astronaut's digestive system, rather than being belched out as on Earth, and may cause adverse side effects.
Published by NASA FTCSC