I admittedly used 2 minute cubes (in comparison to the rest of the soap) of white M&P with no additives in the vanilla-stabilizing soap because it was just too transparent for what I was trying to achieve. That could have played a roll in the soap slightly darkening. The plain soap has darkened considerably. It's almost taken on a grayish hue. It's still perfectly good soap, but it's just not as pleasing to the eye as the original. The soap with the vanilla stabilizer added still looks yellow and beautiful after 3 days. I'm most pleased. I'll be using this method from now on. I can still use the vanilla-stabilizing soap for other projects, but just not this one.