Milk soap, freezers, and saponification

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Well-Known Member
Oct 10, 2022
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Hi everyone!

Made my first ever batch of a full milk soap (frozen goats milk used to substitute for lye). The lye and oils were at around 75F when combined, and I added 1 tsp of honey and 1 T of colloidal oats to the oils. I also used 20 g of a vanilla fragrance oil.

The loaf went into the freezer for about 5 hours, then the fridge overnight. Put it on the counter this morning, and did a quick zap test. Now I know what 'the zap' feels like! The loaf is nice and creamy, no cracks or crumbles from what I can see, and I'm fairly certain my oils and lye were measured correctly (have made this recipe a few times, there's a 5% superfat, and there should have been even a bit of extra fat from the goat's milk).

My question is: Is it common that the saponification process will slow down for a soap like milk soap being placed in the freezer/ fridge? Is it time to panic, or should I just let the loaf sit out and cure for a few more days before re-checking? Glad I made this as a small test loaf!

If you did not let your soap go into the gel phase the answer is yes it can take up to 72hrs to become non-zappy. This also goes for soap batter that is poured just at emulsification. It is almost like the light switch is turned off at the 72 hr mark. Patience...
Oh what a relief!!! Yes, the soap did not go into gel phase. It was my first time using this freezer/ fridge method, and the soap is a lovely uniform creamy colour. I'll just wait 3 days before checking again!