The city of Seattle allows some types of small farm animals to be kept on urban lots, including pot-bellied pigs, miniature goats, and chickens.
Last spring I sold soap at a Goat Festival put on by Sustainable NE Seattle to benefit Seattle Farm Co-op. One of the goats had recently been treated with antibiotics. When the goat herdess extraordinaire offered me the ‘tainted’ milk for making soap, I was eager to make the attempt.
As I have described previously, cold-process soap is made by adding lye dissolved in water to a mixture of warmed oils (about 100F). When goat milk is substituted for water, the extra fat from the milk lends an extraordinary creaminess to the resulting soap.
The unique challenge with goat milk soap is preventing the milk sugars from caramelizing. Dissolving lye is a highly exothermic reaction (heat-producing). Usually the lye-water mixture is placed in a cold water bath during dissolution to help the mixture cool down faster (and avoid melting any plastic containers!).
To avoid the caustic-orange of burned sugars, I froze the goat milk in appropriate-sized batches (42 oz for 120 oz of soap) and tried dissolving the lye in a goat milk slush on soap day. The mixture still turned orange, but the final bars are a lovely tan.
I have been really impressed with this soap. It is extraordinarily creamy, but leaves your skin feeling fresh. Particularly excellent in the winter!