It makes absolutely no difference what color you use as a visual representation. All that matters is what that color inspires in you.
In some cultures, white is seen as death and have a "negative" feeling to it. As such, people of this culture would not use white to do anything they consider "good".
The color of the energy doesn't matter. The intention does. I can summon a demon while picturing my energy as hot pink just the same as I can heal while visualizing the energy to be black.
It's simply about what those colors mean to you, not anyone else.