I recently did a cake with teal buttercream icing. It was difficult to smooth because if I used water...later, little white streaks would show up....how do you smooth buttercream colors?
I usually only have requests for white....white...white...this one was very challenging!
Thanks in advance for your input.
The problem you encountered is due to excessive stiring. When you added the color you probably added a little at a time and kept adding so you stirred it up over & over.
That is what usually causes the white streaks you talked about.
The other thing that might contribute is the wrong shortening. I know everyone is having problems w/these new no transfat stuff.
Use Viva paper towels. Once you have iced your cake fairly smoothly, let it crust for a few minutes, then lay a plain white Viva(it has to be Viva, it's the only one that has no texture), and use a fondant smoother to rub out any imperfections. HTH!
when you say you're getting white streaks when you use water, and you also mention smoothing .... are you using the hot knife method to smooth by wetting the knife in hot water, then running the hot, wet knife over the iced cake?
If so .... don't use a wet knife. Wipe the knife dry before smoothing. I learned this the hard way, too, on a blue-iced cake. Nice little streaks where the water from the hot knife had run down the cake.
The best mthod, in my ever so never humble opinion, is let it sit and crust (5-15 minutes, depending on your recipe) then Melvira it.