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Tang and other dehydrated food into space

  1. May 30, 2004 #1
    Why do our space "scientists" send Tang and other dehydrated food into space; to save weight? We take along the water needed to rehydrate the food. Where is the weight savings? In grade school we used to joke about the guy that sent an overcoat to his friend but cut off the buttons to save weight (theyr'e in the pocket, he reminded).
  2. jcsd
  3. May 30, 2004 #2
    Probably to make food storage easier, and to keep the food fresh for a long time. I'm betting that the food is packed into the Space Shuttle long before it's launched.
  4. May 30, 2004 #3
    besides, tang is great stuff =)
  5. May 30, 2004 #4
    Where does a space crew's water come from

    The Tang is rehydrated with recycled water. Enough water for a single crew metabolism/hygiene cycle in the space shuttle/space station is also enough to rehydrate an infinite amount of Tang for that crew. Hence, the Tang does not need its own water and is sent up as powder and further hence saving exactly as much weight as the extra weight of the liquid Tang displaced by the powder.

    Water recycling for a space crew means that all water excreted from the body as urine and as moisture in their feces is collected and filtered so it can be re-used by the crew. Other sources of water for recycling are water that is respired and sweated into the atmosphere the crew lives in and water used for clean-up (hygiene).
    Last edited: May 30, 2004
  6. May 30, 2004 #5


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    Yum :yuck:
  7. May 31, 2004 #6
    You mean they don't eat or drink unitl they have evacuated? I don't think so. The fact is that they announced early in the program, maybe you weren't there but I was, that they did it to save weight. Recycled water comes from water ingested. Why not eat good food and drink good juice first? Why bother with all the work of reconstituting juice and food. As I recall they spent millions developing a method of inserting the water without spilling. The answer is NOT recycling. The answer is not analyzing the situation properly.
  8. May 31, 2004 #7
    This page has some information on the foods that shuttle astronauts eat and drink in space:


    "One way weight can be conserved during launch is to remove water in the food system. During the flight, water is added back to the food just before it is eaten. The Shuttle orbiter fuel cells, which produce electricity by combining hydrogen and oxygen, provide ample water for rehydrating foods as well as drinking and a host of other uses."

    The astronauts also have more than just dehydrated foods available to them. Here is an astronaut's menu from a previous shuttle flight:


    It looks to me like for any given meal, only a few items are truly "freeze dried." This page outlines some different food types:


    I think the situation has probably been pretty well analyzed.
    Last edited by a moderator: Apr 20, 2017
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