Re: Where do glucose, fructose, dextrose and sucrose come from industrially?

I've never heard of glucose and dextrose being labeled separately on the 
same label.  They are the same compound and labeling in the United States 
would allow for the use of either name...it's merely a preference.  I don't 
know the labeling laws in Canada.  

Fructose and glucose are the monosaccharides that make up sucrose, a 
disaccharide.  However, the two are not commercially derived from sucrose. 
Sucrose commonly comes from sugar cane which is somewhat expensive and not 
widely available compared to other sources.  Therefore, deriving glucose 
and fructose from here would be very costly.  As far as I know, most 
glucose and fructose is derived from corn.  Corn starch, which is a polymer 
of glucose molecules can be enzymatically degraded down to pure glucose 
(with many refining and cleaning steps of course).  Fructose is an isomer 
of glucose, therefore, it too can be derived from glucose by using the 
enzyme glucose isomerase which rearranges the molecule to fructose.  This 
is how corn syrup (or high fructose corn syrup) is made.  Starch is 
enzymatically digested to glucose, which is then converted to a fructose.  

Invert sugar is a mixture of glucose and fructose...in this case usually 
derived from sucrose!  Sucrose can be split into its constituent 
monosaccharides with the enzyme invertase.  This mixture is a liquid, 
whereas sucrose is a solid crystal.  A good example of its use in the food 
industry is in soft centered hard candies.  The hard candies are formed 
around a mixture of sucrose (solid) and invertase.  The sucrose is then 
converted to invert sugar inside the candie and becomes a liquid!  Pretty 
amazing how useful enzymes can be.  Hope this helps...