I remember being so disappointed with my first discoloration and decided I would not make anymore soaps with FO's that would cause it; then I decided I could not live without certain FO's and decided to tolerate the tans and browns. I think it is a matter of conditioning yourself and learning to embrace brown soap :wink:
If it's gonna turn brown, I don't think any colorant will change that. Titanium dioxide can help a little in lightening it but it won't "cure" that problem. There are vanilla stabilizers but I've never used them and from what I've run across, they are designed for M&P soaps and not CP. (Maybe someone can correct me on this.)
The selected oils, additives and temperature can have a huge effect also.