Making Bar Soap with Different Solubility Ingredients

Here are the answers to your questions about making bar soap with Aloe Vera Extract and SKIN-DEFENSE® V, calculating ingredient percentages, and product testing.

Mixing Water-Soluble and Oil-Soluble Ingredients

Yes, it is possible to incorporate both water-soluble ingredients like Aloe Vera Extract and oil-soluble ingredients like SKIN-DEFENSE® V into a bar soap formulation. Bar soap is essentially a matrix of saponified oils (the soap) which contains both a lipid phase and a water phase (or residual moisture).

• Aloe Vera Extract is water-soluble. It should be added to the water phase before mixing with the oils (in cold process) or added directly to the melted soap base (in melt-and-pour) at a suitable temperature.
• SKIN-DEFENSE® V is oil-soluble. It should be dissolved in a small amount of the oil phase (in cold process) before mixing with the lye solution, or dissolved in a small amount of melted soap base or added oil (in melt-and-pour) before pouring.

While they have different solubilities, they can coexist within the soap structure, each residing primarily in their preferred phase. You cannot pre-mix the concentrated water-soluble extract directly with the concentrated oil-soluble ingredient and expect them to combine homogeneously before adding to the soap. They must be added to the appropriate phase during the soap making process.

Calculating Ingredient Percentage

Your calculation method seems a bit off. The percentage of an ingredient in a formulation is typically based on the total weight of the final product.

If you want to add SKIN-DEFENSE® V at 1-2% of the total soap batch weight, you calculate the amount needed based on the total weight.

• Example: If your total soap batch weighs 1000g and you want 2% SKIN-DEFENSE® V, you need 20g of SKIN-DEFENSE® V (2% of 1000g).
• This 20g of SKIN-DEFENSE® V should then be dissolved in a small portion of the oils that are already part of your soap recipe before you combine the oil and lye phases (in cold process) or before adding to the melted base (in melt-and-pour).
• The oil used to dissolve the SKIN-DEFENSE® V is part of the total oil amount in your recipe. You are not adding an additional 1-2% of the dissolved mixture on top of the base percentage. The 1-2% is the final concentration of the active ingredient (SKIN-DEFENSE® V) in the finished soap.

So, if you want 2% SKIN-DEFENSE® V in your final soap, you add the amount of SKIN-DEFENSE® V equivalent to 2% of the total batch weight, dissolved in a suitable oil carrier.

Product Testing for Skin Irritation

To test your finished soap product for skin irritation or conduct other product testing, you would typically use a third-party testing laboratory that specializes in cosmetic product testing. These laboratories can perform various tests, including:

• Patch Testing: This is a common method to assess skin irritation and sensitization potential on human volunteers.
• Stability Testing: To check how the product holds up over time under different conditions.
• Microbiological Testing: To ensure the product is free from harmful microorganisms.

You can search online for cosmetic testing laboratories in your region or country. Look for labs that are reputable and follow standard testing protocols.