Some people use cocoa butter as a substitute for lanolin in shaving soap.
Shaving soap has a high stearic fat/oil acid content and is more stable than regular soap. Lard and tallow contribute to a stable lather. 40 to 50% fat level is optimal for a good soap.
What Does Lanolin Do In Soap?
Lanolin is used in soap. It’s great for dry skin types. You can read more about the benefits of lanolin in this article. Some soapers say that their soap has a strong smell, but that might be the type they’re using. 
What Does Lard Do In Soap?
Lard and tallow contribute to a stable lather. Both tallow and lard are used as substitute for palm oil. You can buy lat and tallow from the store or make your own at home. 
What Ingredients Are In Shaving Soap?
Shaving soap has a high stearic fat/oil acid content and is more stable than regular soap. The stable lather, slickness, and softened qualities are needed in a shave soap. 
What Makes A Great Shaving Soap?
The triple milled hard soaps cost a little more, but they are usually the best shave soaps. 40 to 50% fat level is optimal for a good soap. Good lubrication and skin protection can be provided by a high percentage of fat. 
Can We Make Soap With Butter?
Yes, it makes a difference, but you can keep it simple and still get a great result. The qualities of your bar of soap will be affected by the raw ingredients you choose. 
What Butters Are Good For Soap Making?
Cocoa butter, kokum butter, mango seed butter, palm oil, and sal butter are some of the ingredients that contribute to a creamy lather. Iodine predicts the strength of soap. 
How Much Castor Oil Do I Put In Shaving Soap?
In cold process soap, castor oil is used around 2% of the total oil weight. I’ve found that using more than 10% can cause a sticky bar. A small amount of castor oil contributes to a stable and fluffy lather. 
Frank Harmenstein is the lead editor of the grooming website Cut Throat Straight Razor, and has over 15 years of experience in the industry. He’s personally tested and reviewed over 200 different straight razors, and has written countless articles on the subject.