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Need help dehydrating liquid fruit blends

  1. Mar 11, 2014 #1
    I am trying to understand the best way to dehydrate water from a liquid slurry fruit and vegetable blend, without loosing any of the vitamins and nutrition from the slurry. I expect to very thinly spread out the fruit/vegetables on a sheet, use dried convection air to help with the dehydrating, but keep the temperature of the slurry below 130 F.

    Beyound using heat to evaporate the water, are there any othe ways to just cause the water molicules to more readily evaporate without damaging the nutrient content of the fresh fruit/vegetable slurry and preferably using low cost energy; microwaves, light wavelengths, radiant heat, sound waves, added solutions, , etc. Just looking for some idea/suggestions to investigate.

    Thanks in advance,

  2. jcsd
  3. Mar 11, 2014 #2
    Vacuum or freeze drying
  4. Mar 19, 2014 #3
    A combination of both freezing and then applying a strong vacuum would do the trick. This is what is termed 'freeze drying' and used in the food industry to prepare dried food stuffs. When a vacuum is applied to the frozen food, the water content sublimes from the solid state to the gaseous state without going through the liquid state.

    This is also a good way to save important books, photographs, documents etc, from water damage if they've been flooded. It is advice given out by the National Library of Canada if a library, , or similar facility has been flooded, say when the building's plumbing fails. The first thing you should do is put the books in a deep freeze/ freezers then arrange to have them processed by a freeze drying facility. (that's the expensive part...)

    Or until one can get a hold of a vacuum pump and build their own DIY vacuum chamber(s)...

    The upside of freeze drying food is that there is almost no nutrient loss compared to heating the food.

    There's probably a wiki entry about this subject....
  5. Aug 3, 2015 #4
    I have also read that freeze drying is the best way to salvage wet books. I am in that current predicament! I have found some instructions on creating a vacuum system (http://www.tk560.com/phpBB2/viewtopic.php?t=424), but what I can't seem to figure out are the qualifications for the vacuum chamber. The examples cite water heaters, etc., but to my knowledge, the examples cited cannot be opened to place books inside. Could I attach the vacuum system to a cooler/ice chest, or would it implode under the pressure or leak? Could I simply place dry ice in or around the cooler to achieve the desired temperature?
  6. Aug 4, 2015 #5


    User Avatar

    Staff: Mentor

    What you are asking is more of an engineering problem than chemistry, I suggest asking your question somewhere in the engineering subforum.
  7. Aug 4, 2015 #6
    Will do, thanks.
  8. Aug 4, 2015 #7
    You do not say what do you want the final product to be, in other words how much dehydration do you wish to achieve - a concentrate, a powder, a juice, a blend of juice and pulp, etc. Can determine the type of processing you need.
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