Every kind I use ends up drastically changing the taste of the frosting...especially if I need a deep color!
Any suggestions/websites that sell no-taste food coloring?
I use the AmeriColor brand all the time for ALL colors and I've never noticed any change in the flavor of my buttercream. It's great for fondant too! The main reason I think it doesn't add flavor is because you don't have to use as much as most other brands, so you're not pumping so much chemical into the icing. Works for me!