What caused this discoloration?

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Made a 34 oz. batch using: 48% lard, 31% olive oil,16% coconut oil, and 5% castor oil. Fragrance is Crafter's Choice Guava Fig which is expected to discolor to "light yellow" after cure. I added goat milk powder and 2 Tblsp honey at trace. To the main batter I added 2 Tblsp dispersed TD (which would have been 2 tsp TD powder) to counteract the discoloration. Preheated oven to 170 and turned it off when I put it in for 2 hours. I was surprised at how brown the supposed-to-be-white part of the soaps turned out. Do you think it was the goat milk? the honey? the CPOP? something else?

Also, I've been using 33% lye solution but I've notice that since our Pacific Northwest rainy season has begun, my soaps are holding a lot more moisture and needing more cure time. I'm thinking to cut back on the water in future winter batches and try 35% lye. Cool damp weather doesn't seem to be my soap's friend.

Thanks for any insights you can offer on this!

PXL_20201218_190838503.jpgPXL_20201218_190756959.jpg
 
Your culprits:
The honey- discolors tan/light brown
The milk- discolors yellow, on average
The FO- discolors light yellow
All of these on top of each other cumulatively would result in medium brown.
Gelling deepens all colors by causing the soap to absorb more light instead of reflecting it, so it has enhanced both your Micas and your discoloration.
 
I can't tell from your words whether you realize that TD won't ever turn a colored soap into white, even if the color is a pale shade. All it will do is lighten the base color. So if the base color is a tan, then adding TD might turn that into a light tan or beige, but you won't ever be able to add enough TD to make the soap white.

Another thing I want to share. Many people have found the CPOP method where you heat the oven to 170 F is often too much of a good thing. It's easy for the soap to overheat when the oven starts out that warm. Try heating to 140 F, turning the oven off, and CPOPing your soap that way.

Many ovens don't allow you to preheat to that low of a temp, so the work-around is to put an oven thermometer in the oven, turn it on to the lowest temp you can use, and then preheat until the thermometer reads 140. Once you know how many minutes it takes for the oven to reach 140, you can just use a timer for preheating.
 
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I can't tell from your words whether you realize that TD won't ever turn a colored soap into white, even if the color is a pale shade. All it will do is lighten the base color. So if the base color is a tan, then adding TD might turn that into a light tan or beige, but you won't ever be able to add enough TD to make the soap white.
I was thinking that since my base oils were high lard content and the FO discolored only to a pale yellow, the TD would be able to dial that back. Turns out it didn't stand a chance with the honey and goat milk powder.

@Peachy Clean Soap Thank you :) I don't really mind the tan, it was just a real surprise. I was going to call the soap Guava Rain, but now I'm calling it Honey Guava to match its color (haha)
 
From my opinion you should put the bar immediately in freezer as you used milk and honey. You increased light burning of the milk by putting in oven. I advise you in the future when you notice an increasing in temperature after adding lye to oils put the soap in the freezer for two hours
 
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