With heat and or time HMF (hydroxy-methyl-furfural) is formed in
honey. This compound is what makes honey un-usable as feed for
bees.
See this link for some limited info
http://www.xs4all.nl/~jtemp/hmf.html
As a rule I only feed back honey from the current year. Why take a
chance when you can buy corn syrup for around 15-20 cents a pound?
The only use for large quanitities of old honey that come to mind
would be to sell it as bear bait during hunting season or if you sell at a
farmers market as bottom feeder bait (folks looking for cheap honey
where price is the only factor in their buying descision)
-- Visit www.honeybeeworld.com/bee-l for rules, FAQ and other info ---