Re: 10 year old honey with slight fermented smell
Welcome to Beesource!
Honey weighs about 12 lbs per gallon (compare to water at 8.3 lbs), so its not surprising the barrel is 'heavy'.
Difficult to say what you mean by 'viability' of the honey. Most likely it is fine to feed back to bees, or to make mead from. Most likely, it will be fine for humans to eat also, but whether the taste of what may be slightly fermented honey is appealing is a personal choice.
Honey can generally be de-crystallized by warming it.
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