Good question. I sent Wintersun an email and below is their response.
Mike
They are natural Thyme plant extract.
Thanks
Best Regards
Michael Shen
Director
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Last week I asked Michael Shen if the Wintersun product looked like "tiny beads" and he said it does. Lebermuth's thymol looks like very small beads if it means anything... With a price that is very close to Lebermuth's I would wonder if the Wintersun product was 100% natural.
A sales person at Lebermuth confirmed that their product
did not contain any natural thymol... it is 100% synthetic (flavor grade). I was also told that "natural thymol" is 3 or 4 times the price of synthetic. If that's true I would ask Wintersun to provide evidence showing that their product was 100% natural.
I believe that the natural product would be much more expensive, but is it possible that Wintersun's product sells for about the same price as Lebermuth's?
I have
only used thymol in late summer/fall syrup to prevent fermentation. My bees are about 40 minutes away so I top-off the feeders when I make a trip over to inspect them.
For the minimal amount that I would ever use, I think I would just buy the U.S.P. thymol sold by "Medichest".
http://www.medichest.com/thymolcrystalsnf100gram.html