Adding Water-Soluble Ingredients to Soap

Regarding your questions about adding water-soluble nourishing substances to soap:

1. Adding water-soluble ingredients separately and combining later: Generally, water-soluble ingredients are added to the water phase during the initial formulation process before saponification. Trying to add them to finished solid soap and combine with an emulsifier is typically not an effective method for incorporating beneficial actives into the soap matrix. Solid soap is a different system than emulsions.

2. Melting finished soap and adding ingredients: While it is technically possible to melt finished soap, adding heat-sensitive or pH-sensitive nourishing substances at this stage is not recommended. Finished bar soap has a high alkaline pH, and melting involves heat. Most beneficial skin-nourishing ingredients are sensitive to high pH and heat, which would likely degrade their quality and effectiveness quickly in the soap environment, as the staff reply also noted.

3. Sea Kelp Extract availability: Based on the information, Sea Kelp Extract is a product that is available. However, as the staff reply mentioned, it is currently out of stock but expected to be restocked soon. This is why you were unable to order more than 20g. Sea Kelp Extract is water-soluble and should not be exposed to temperatures exceeding 60°C, which further supports why adding it to hot, melted soap is not advisable.

For adding beneficial ingredients to soap, it is often better to consider ingredients that are stable at high pH and temperature, or to formulate liquid soap or other cleansing products where the pH can be adjusted after adding sensitive actives.