Cold Process Soap Fragrance Testing

Crafting high-quality cold process soap requires understanding how various factors, including fragrances, interact with your recipe. To better support our soapmaking community, we’ve refined our testing methods to reflect a broader range of real-world scenarios. While we previously used a slow-moving recipe for testing, we’ve transitioned to an average-moving recipe for a more balanced approach.

As of 2025, we’re reviewing all our soap-safe fragrances using this updated recipe. It will take us time to go through all of our fragrances, so we ask for your patience. 

You can find detailed results for each fragrance on its product page. These results are designed to provide helpful insights, but please remember that your own results may vary depending on your specific ingredients, methods, and conditions. We will label any revisions with a testing date on the product page to alert you to what recipe was used for testing.

Below, we outline our updated testing process so you can better understand the context behind our results. Happy soapmaking!

Our Revised Process

• We test fragrances at 5% unless IFRA requires that we test lower. 
• With our revised reciepe, Blended the oils and lye water at 110ºF or lower.
• Used silicone loaf molds and do not cover soap.
• Use a 2:1 water / lye ratio
• Used minimal insulation, typically only two to three molds sitting side by side on a wire rack. This helped us test for overheating and observe if gelling occurred.

We unmolded the soap between 24-72 hours, then cut them. We documented scent strength, changes in odor, and any discoloration. We allowed the bars to cure on a wire rack for four weeks and then checked for scent strength, discoloration, and changes in scent profile.

Pre-2025, we only tested fragrances that were allowed by IFRA in Category 9 at 5% or higher. Going forward, we will test fragrance with an IFRA category as low as 2%. 

Before running your own tests, be sure to review the IFRA certificate for maximum usage levels on the product page. Using more or less fragrance may produce different results in your final product.

Once the soaps cured, we saved one bar for reference and donated the others.

Have a question?

If you have additional questions please reach out to us at [email protected].