Hi Harriet:
I realized that I did not answer the second parts of your question- Can you use beer and evaporated milk with butter as substitutions for liquid in making soap?
Beer - Beer can be used with great results. Beer makes a fantastic men's soap. The aroma (depending on the brand) can be heavenly! Here is the link to a
Beer Brew Recipe. One thing to
note though - is that the beer has to be flat before using it instead of water in the recipe.
Evaporated Milk - Evaporated is made from homogenized milk with
60% of the water removed. To reconstitute, add 60% water. Evaporated milk can be used instead of water in soapmaking - the results should be similar to soap made with whole milk or cream. I would imagine that a small amount of butter can be melted in with the evaporated milk which would then be counted as superfatting or to mimic half and half or cream in the recipe. Here is a recipe for milk/cream/half and half soap -
How to make soap with frozen half and half.