Natural Colorant Darkening after cure
(Seattle, WA, USA)
I use a soap recipe that is tried and true. I use a wooden soap mold that I insulate with a blanket for the first 24 hours.
I recently started using natural colorants and noticed that after I have released them from the box (after 24 hours) and cut them, the color is vibrant and lovely. Then, 2 days later, the colors settle to muddy browns or yellows. I can see a brown ring around the outside of the soap and just know that the whole bar will be this awful color in a matter of days.
No cracking, dusting or other problems.
Is this overheating possibly?
I have been using paprika and turmeric added at trace.
What scent are you using? Most fragrances that contain a vanilla or coconut component will turn the soap a brown colour.
Unfortunately many rich and exotic scents do contain these components.
To avoid these unpleasant surprises, join the Soap Scent Review Board to see if there are any reviews on your scent. Often the supplier will give reviews as well. You can also do test batches to see how a scent holds up in your recipe.