Well I started off studying pollen spectra trapped in plaster and such from various biblical cities in Israel, but a few years ago I developed a method for extracting pollen from various non-polar resins used as adhesives in the prehistoric southwest (
Pinus, Lac insects,
Encelia etc etc). During my time doing all that I honed my own method for extracting pollen from honey, which is chemically a lot easier than non-polar resins, and tested quite a few random samples of honey for various people.
In regards to the actual data that can be obtained from this type of study, I use various keys and reference collections to identify and get a count of pollen grains (100-200 grains counted per sample usually) then use that information for whatever study i'm performing. The actual amount of pollen that makes it into the honey varies depending on the race of
bees and the individual hives, some are better at filtering out pollen that falls into the nectar that they eat than others. I'm not too sure about the pasteurization thing since pollen is actually extremely tough and I'm not sure if it would show much evidence of heating, though if a honey has been illegally imported or something and its origin is hidden it might be centrifuged of its pollen in order to keep people (like me haha!) from discovering and questioning the products origin.
I do think that if one could keep track of when honey was made and deposited by the hive I can also get much more accurate results for a specific time frame. I theorize that (for example) if a hive dies seemingly out of nowhere I could take a sample of the last deposits of honey and such and indicate what the bees were foraging for prior to the death of the colony, maybe giving some extra clues as to why. There may also be a difference in the spectrum of pollen in bee pollen and the honey made at the same time because of preferences in nectar vs. pollen resource plants and availability of protein and such of each.
Many many things one can do with it and the sky is the limit.