Hello ~ I don't claim to be an expert but in my research of milk soap recipes I learned that a common problem is scorching of the milk when combined with lye, hence 3 possible solutions:Most of the recipes I stumble on, that feature Goat's Milk, always have the milk frozen. They either combine it with the sodium hydroxide in place of water, or add the frozen milk with the melted oils. I've only used this milk a few times and I've never frozen it and only added it to the oils. After curing a batch for a minimum of 4 weeks, I tried the bar and it was a very creamy soap. I was really happy with the result. Can anyone tell me what advantage freezing the milk has over not freezing it? I assume the high temperature will affect the quality of the milk but are there any other reasons?
I've made over a dozen batches of soap and I've never measured the respective oils and lye solution temps. Why is it important to do this? Does false trace have something to do with this (i.e. decreasing the likelihood of it occurring?)
1) freeze your total weight of milk, then add your lye to the frozen milk, which will thaw the frozen milk and keep the lye temperature low (and also minimize the lye fumes). It takes a few minutes of alternately stirring and letting it sit for the lye to thoroughly dissolve and then it's ready to add to your melted oils.
2) Use an ice bath to control the temperature of the milk and lye solution while stirring. Personally, I find this awkward to set your lye solution bowl inside a bowl full of ice while stirring. It was literally the only time I experienced a lye splash because my bowl was moving around inside the other bowl, but to each their own
3) Adding the milk to the oils instead of the lye solution. For this option, the milk would only represent a portion of the liquid/water required for recipe, whereas in the 2 methods mentioned above it can represent the full amount of your liquid. For this method, you take your liquid required for the lye solution and subtract a portion, adding it as milk to your melted oils and mixing your lye solution with the remaining amount of water.
I hope this helps with understanding the different processes. Really, they are just ways to help minimize the potential for scorching, which can occur with any milk in a soap recipe, to my understanding.
Happy soaping