There can easily be another problem with drying sucrose: dehydration (by 
which I mean CH2O -> C + H2O).  I've dried samples at less than 100 degrees 
C and, in the presence of some impurities, they have dehydrated 
(caramlysed) quite substantially.  Even traces of acid will do this, for 
example.  Phloem samples have also shown that behaviour.  Vacuum drying 
produces the effect at even lower temperatures.  For example a student here 
vacuum dried a 0.01 molar solution of HCl and sucrose at room temperature 
and produced something fit only to be mixed with custard.

Is there an associated fractionation?  I don't know.


Hilary Stuart-Williams PhD
Research Officer
Environmental Biology
Research School of Biological Sciences
The Australian National University
Canberra, Australia ACT 0200
Telephone +61 2 6125 2099
Fax +61 2 6125 4919