Sodium lactate and brown spots

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Active Member
Jan 28, 2015
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Raleigh, NC
I made a soap and separated out part of it. I added sodium lactate at about 3% of the weight of the oils in that part. And, I used a green colorant. So, the soap that came from this part of the mixture turned brown about a week later. The soaps that came from the other part of the mixture (with no sodium lactate and a camel colored colorant) didn't become brown. Not only did the soap turn brown but where it was touching another soap it turned the other soap brown too. Any ideas what happened?
Did you scent it with anything? Certain FO's are notorious for turning soap brown.

For what it's worth, I use 3% sodium lactate (in a pre-mixed 39% solution form) in almost all my batches and it has never caused browning of my soap.

What type of green colorant did you use?

IrishLass :)
I too have never had SL turn my soap brown and I use it in almost every batch. It may have been your colorant not being CP stable. It's such a bummer when things don't go as planned.
Thanks everyone. I decided it must have been that the lime green colorant I used wasn't well-suited to whatever the ph was when I added it. The camel colorant that I used on the other portion of the batch was fine with it. Glad it wasn't the Sodium Lactate. That stuff makes the bars shape so beautifully and I love the significant improvement in bubbles!