In order to avoid any legal ramifications, it's suffice that this is Willy's healthy supplement recipe for adding to sugar syrup.
5 cups water
2 1/2 lbs sugar
1/8 teaspoon lecithin granules (used as emulsifer)
15 drops spearmint oil
15 drop lemongrass oil
He mentioned he used a cap full per 2 gals of sugar syrup when feeding.
Willy purchases the lecithin granules and oils from Puritan's Pride. www.puritan.com (This is not an endorsement, but just a source suggestion)
However, the least expensive container of lecithin granules is 16 oz which is most likely a lot more than will ever be used by one beekeeper. Amazon has a 4 oz package available which is reasonable even though the price per oz is a good bit more.