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Why does candyfloss absorb more moisture faster than grain sugar?

  1. Jul 21, 2014 #1
    Does it have to do with sucrose decompose into glucose and fructose or surface area? Caramelization occurs when sugar start to melt, so does it have to do with caramelization?
  2. jcsd
  3. Jul 21, 2014 #2


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    Are you heating your candy floss to caramelization temperature?
    Or is it at room temperature?
  4. Jul 21, 2014 #3
    I heat it, so it would melt.
  5. Jul 22, 2014 #4
    How were your tests arranged?
    But if you heat these sugars well above boiling temperature of water, there should be less water adsorbed, except you led both sugars cool down and give them time to adsorb water.
  6. Jul 23, 2014 #5
    I noticed it when I made candy floss, it becomes sticky after a few minutes.
    This can be replicate by melting fine sugar then let it cool and harden, after a few hours it will absorb moisture and dissolve it self.
  7. Jul 23, 2014 #6
    Without weighing the adsorbed moisture, there can be no serious evaluation what happens. As you write, the surface area is important about the speed of adsorption as diffusion distance is short. But i can not give any clue about the influence of caramelization.
  8. Jul 23, 2014 #7
    Thank you. But I think that it have to do with fructose and glucose.
  9. Jul 23, 2014 #8


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    Originally I was not sure what you were asking about. But now I understand you are asking about the candy becoming gooey from humidity - an important question in the candy making industry where one does not want the candy to become gooey to the touch all too soon, if at all.

    Even important in sugar transport, where one does not want the sugar to cake together and become one big lump. For table salt, the processors add calcium silicate to keep the salt crystals free flowing, but for table sugar that most likely does not work, as at home my sugar has been known to lump together ( I don't have a bag of sugar to check for additional ingredients ).

    http://www.thaiscience.info/journals/Article/Effects%20of%20grain%20size,%20reducing%20sugar%20content,%20temperature%20and%20pressure%20on%20caking%20of%20raw%20sugar.pdf [Broken]
    someone has done a bit of research on raw sugar.
    They mention temperature, relative humidity, grain size, and the presence of reducing sugars as factors.

    Reducing sugars
    would become syrupy and sticky with moisture, and one has the glucose and fructose acting reducing sugars, present from the caramelization of sucrose.

    You can follow those leads and see what the candy industry does to their products to combat stickiness.
    Last edited by a moderator: May 6, 2017
  10. Jul 24, 2014 #9
    Thank you very much, I appreciate it.
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