Hi again. As far as I know, erythritol is normally combined with other sweeteners. For example, the liquid stevia I buy (which is a store brand) has erythritol listed as the first ingredient - which means to me that there's more of it than the stevia.
Check the ingredients of these artificial sweeteners and you might find it in some of them. Here is some information I found about
it:
lowcarbdiets.about.com/od/products/p/erythritol.htm