Soap Un-discolors When Wet

[The_Emerald_Chicken]

These two bars of soap are from the same batch, made in November. They're fragranced with BB's Espresso FO, which has a 3.5% vanilla content and discolors to brown. After using a bar for a while, I've discovered that the discoloration reverses, at least somewhat, when the soap is wet (the bar on the left). When it dries out, it gets darker again (like the new bar on the right).

Is this common for soaps with vanilla discoloration? Anyone else experience this?

 

[Peachy Clean Soap]

View attachment 52927
These two bars of soap are from the same batch, made in November. They're fragranced with BB's Espresso FO, which has a 3.5% vanilla content and discolors to brown. After using a bar for a while, I've discovered that the discoloration reverses, at least somewhat, when the soap is wet (the bar on the left). When it dries out, it gets darker again (like the new bar on the right).

Is this common for soaps with vanilla discoloration? Anyone else experience this?

very interesting. Hmm

 

[GemstonePony]

The discoloration is from the FO reacting with the air. Your soap likely isn't that color the whole way through, just at the surface. The discolored portion rubs off when you use it, and then it re-colors again.
I colored a soap with green Mica, then used a discoloring FO that turned it brown. So, I get to glimpse the pretty green when I use it, and when it dries it turns back to brown again.

 

[The_Emerald_Chicken]

Aha! That makes sense. Thanks for the explanation, @GemstonePony !