I have had this happen with lemongrass EO too just recently... same soap recipe both times, it happened when i let it gel and it got pretty hot when i insulated it.
Can you tell if this is what is happening to you also? I'd love to get to the bottom of it!
I did the same recipe with different EO's and let it gel with no problem, ( a tad moist when first unmolded) and the same recipe without gel, and it was fine, but took a day longer to firm up. (I've been doing this recipe a LOT to practice, since it is slow to trace and doesn't usually get too hot, so I'm trying to learn swirls.)
But when this recipe gels with the lemongrass for some reason, it gets a layer of oil or something on top afterward. The oily stuff is mostly flavorless, no zap, a tad sweet with the barest tiniest hint of the lemongrass, but i might as well be tasting grapeseed oil, that's the consistency and feel of it, except there's nothing like that in the recipe.
The soap is fine, firm enough to cut, no zap, etc. The first time i wiped it off, the second time i left the oils sit on the parchment and left the cut bars sit on it, and the next day the bars had reabsorbed most of the oils. It was weird.
Should i just wipe it off when that happens? Let it soak back in? SF less? This was 7% SF, and like above, it was a simple mostly OO recipe, with some castor and coconut oils, full water. Madder root color in half, and plain no-color in the other half, .5oz lemongrass ppo.
I am seriously curious about this! The soap is turning out fine, feels nice when I lather it up, not drying, not sticky... let a co-worker try some, he has eczema same as me, and he loved it also. So it doesn't seem to be hurting anything other than being annoying and messy. But i could do without that lol.
The finished scent is very strong, (which i love) even at .5oz ppo and even with it leaking out like that... could I still be using too much? Could this be glycerin? It is a tad sweet. I haven't tried HP yet but i read that when it cooks you have to stir the glycerin back in?
ETA - i also used the lemongrass EO in a batch that was mostly lard, and i got a thin coating of the same oily stuff all over the loaf after gel, which reabsorbed within a few hours after unmolding and cutting. That batch had no OO and only 5% SF. Same level of EO's.
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