I read recently that the chemical properties of honey make it very easy to preserve (there’s a term, but I don’t remember it). The book even mentioned that archaeologists who found honey in jars in a tomb ate it and it was good, but I can’t find any more information about this. Anyone know?
http://www.newton.dep.anl.gov/askasci/gen01/gen01338.htm
http://anubis4_2000.tripod.com/SpecialExhibits/Weigall.htm
The preservative idea behind honey is the same as that behind pickling, or curing, or fermentation, or vacuum-sealing, or canning: the microbes that cause decay generally can’t tolerate extreme environments… environments that are too sweet, too acidic, too dry, too alcoholic, too airless, or too hot (*). Therefore, honey is safe from decomposition caused by nasty little buggies; they won’t touch the stuff. It can oxidize (slowly) but being stored in jars helps prevent that. It can decompose due to energetic radiation (i.e. sunlight) but being stored in dark tombs helps prevent that, too. So I’m not at all surprised that ancient honey is still edible. What’s going to happen to the honey to change it?
(*) “Too hot” is in the eye of the microbe, and for that matter so is “too airless”. Some bacteria, notably Clostridium botulinum, can survive at boiling-water temperature, and are quite happy in an oxygen-free environment, too. Therefore meat must be preserved with a pressure-canner to be safe.
It’s not really a chemical property, it’s just that it’s too dry. All the water in honey is absorbed in a matrix with the sugar, which makes it unavailable for microbes to use.