"Glycerol Ester of Wood Rosin"??

i have always considered gatorade to be "okay", not great, but ok. well yesterday i read the ingredient list on my lemon lime gatorade and it says "glycerol ester of wood rosin"?

doesn't sound good to me, and i never noticed it before. does anyone know anything about it? wood rosin i know, and glycerol is a sugar/alcohol product, do they combine to do something toxic? do they have to ruin EVERYTHING??