> This statement brings two questions to mind:
> 1) How hot do you have to get wax to kill AFB spores? If they can survive
> the temperature needed to melt wax for foundation production then I wonder
> how often beekeepers have installed spores along with new foundation.
> 2) Since the reason given to pasteurized honey is to kill botulism, and I
> understand that botulism is a spore producing bacteria, what is the gain?
>

When I was taking microbiology, we were taught that the only way to be sure
of killing bacterial spores was to autoclave at 121 deg. C for at least
fifteen minutes, or dry heat to 160-180 deg. C for between 1.5 and 3 hours.
It sounds like both AFB and botulinium spores are pretty typical, so
these figures probably hold good (I checked these values in my old lab
manual, by the way).

It sounds like, for using heat to kill AFB, we have to stick with the old
standard method: Burn the combs and frames, carefully scorch or burn
the woodenware, bury the ashes.  It's the only way to be sure.

And as far as pasteurizing the honey: you are right. There is no gain.
To kill botulinium spores, you have to use a pressure canner (which is
a small autoclave, incidentally).  Pasteurization will not do it.
Pasteurizing honey only kills the vegetative (actively growing) cells,
and as long as the moisture content is low enough, nothing actively
grows in honey anyway.

There is a process, called "Tyndallization", where you can use multiple
heat cycles to convert spores into vegetative cells, then heat enough
to kill the vegetative cells.  However, it only works if the cells can
grow in the material you are trying to sterilize in the first place.
Again, since nothing grows in honey, Tyndallization won't do any good
either.

So, to sum up:

1. You need temperatures above the boiling point of water to kill
AFB spores. Burn it all to be sure, don't take chances to try and save
a couple of bucks, because it will probably cost more in the long run.

2. Don't bother pasteurizing or otherwise heat-treating honey to kill
bacteria, it won't work and will damage the honey.

Tim Eisele
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