Lloyd asked:

> Does anyone know the reasoning for using both corn syrup and sugar?

Sure.  
Two reasons.

The first reason is to prevent the sugar from crystallizing into
"grainy" crystals.  

Consider fudge, in which crystals do form.
You don't want that to happen to your bee candy.

You want an "amorphous" mixture, more like taffy or caramel.
You want solidification without crunchy crystals.

The (Kayro) "white" corn syrup is, of course, a mix of fructose 
and glucose, which "get in the way" of sucrose crystal formation, 
and allow the mixture to solidify without forming grainy crystals.

Of course HFCS has a lot more fructose than the Kayro, hence the 
name "high fructose corn syrup".  The Kayro could be called 
"low-fructose corn syrup", I guess. Both are made by converting 
some of (or most of, for HFCS) the glucose in cornstarch to fructose.

The cream of tartar is also helping to prevent crystallization
into big ugly crystals.  It will break down (some people call
this "inverting") some of the sucrose into fructose and glucose, 
and those molecules will, like the corn syrup, prevent large 
sucrose crystals from forming.  Its an acid, nothing more.
It is consumed in the breakdown process, so with proper
heat and time, it leaves no residue.

The second reason (perhaps the more important one for this
application, given that one is also adding cream of tartar) 
is that corn syrup is hygroscopic, so the final mixture 
will not dry out and get hard as a rock. The corn syrup 
will tend to draw in moisture from the surrounding air,
and stabilize as a "softer" mixture.

So, you are making really a very lousy kind of "taffy" 
here, and you can adjust your formula depending upon 
how your first small experimental batch turns out.  
Grainy crystals?  Try just a tiny bit more cream of 
tartar, like maybe 1/8th a teaspoon. (The stuff never 
"goes bad", so don't worry about the fact that you 
bought it back when Nixon was president.)

Too hard a final product?  Don't make your bees work
so hard for a meal, add some more corn syrup.

Now marshmallows are the softest thing around, and they
use the same exact tricks, but they also use gelatin to
make the ultimate "soft candy", and we don't want 
anything in the final mix for bee feed except sugars.

And why do I know all this stuff?  No, I wasn't paying
attention in chemistry class, either. It is just that 
am likely the only guy here who owns 4 different wisks, 
and has a detailed rationale for the advantages of each.  :)

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