Cold process soap making is a traditional method that involves combining oils and lye to create soap without the need for external heat. If you're interested in making cold process breast milk soap, you can adapt the basic cold process soap-making technique to incorporate breast milk as one of the ingredients. Here's a general outline of the process:

Please note that making cold process soap requires working with lye, which is a caustic substance. It's essential to follow proper safety precautions, including wearing protective gear like gloves and goggles and working in a well-ventilated area.

1. Gather ingredients and equipment: You will need breast milk, a lye solution (sodium hydroxide mixed with water), carrier oils, such as olive oil or coconut oil, and any additional ingredients like essential oils or herbs. Additionally, you will need soap-making equipment, including a heat-resistant container for mixing, a stainless steel or heat-resistant plastic mixing spoon, a soap mold, and safety gear.

2. Prepare the breast milk: Thaw frozen breast milk if using, ensuring it's fully defrosted. Keep in mind that breast milk contains sugars that can accelerate the saponification process, so you may want to use a reduced amount of breast milk compared to other liquids in the recipe. Experimentation may be necessary to find the right ratio for your specific soap recipe.

3. Prepare the lye solution: Carefully measure the required amount of lye and water according to a reliable soap recipe. Slowly add the lye to the water, stirring gently until it dissolves. Be cautious as the mixture will release fumes and generate heat. Allow the lye solution to cool.

4. Combine the lye solution and oils: In a heat-resistant container, combine the carrier oils and melted fats (if any) with the breast milk. Slowly pour the lye solution into the oils while stirring continuously. Mix until the mixture reaches a thick, pudding-like consistency known as "trace." This process may take several minutes.

5. Add optional ingredients: If desired, you can add essential oils or herbs for fragrance or additional benefits. Stir them into the soap mixture thoroughly.

6. Pour into molds: Pour the soap mixture into your chosen soap molds. Smooth the surface if needed and tap the molds gently to release any trapped air bubbles.

7. Cure the soap: Allow the soap to cure and harden in the molds for about 24 to 48 hours. After that, carefully remove the soap from the molds and place it on a drying rack or a well-ventilated area. Let it cure for an additional 4 to 6 weeks, turning it occasionally to ensure even drying. This curing process allows the soap to fully saponify and become milder and longer-lasting.

8. Test and use: Once the soap has completed the curing process, you can test it by using it on a small area of your skin. If there are no adverse reactions, you can enjoy using the cold process breast milk soap for personal care.

Remember to prioritize safety and hygiene when working with breast milk and lye. It's recommended to consult with a healthcare professional or dermatologist if you have specific concerns or questions about using breast milk in soap or its potential effects on the skin.