> Does irradiation (food grade gamma irradiation) of honey kill all
spores

Yes, it kills everything that might be alive.
The trick is getting the correct beam flux to 
penetrate both the container and the honey.  

I'm not sure why anyone would want to bother to 
irradiate honey if the honey was to be eaten by
humans, and I couldn't think of a more expensive
way to feed bees than to take something very 
valuable, like honey, and add cost by irradiating it.

Also, note that consumers have a very negative reaction
to food that has been irradiated even though the 
process does nothing but good.  (Yet another example of
the price of a of basic science education.)

So, what's your idea here?

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