Adding Special Properties to Solid Soap (Oil-based & Glycerin)

Welcome to soap making! It's true that adding active ingredients to solid soap, especially cold process soap, can be a bit tricky compared to liquid soaps or other cosmetic formats. This is mainly due to the high pH and heat involved in the saponification process of oil-based soaps, which can degrade sensitive ingredients. Melt-and-pour glycerin soap is somewhat easier as you add ingredients to a pre-made base, but the base is still alkaline.

Here are some types of ingredients and their suitability for solid soap based on your desired properties:

For Exfoliation

Physical exfoliants are generally well-suited for solid soaps as they are insoluble particles dispersed within the soap matrix.

• Magnetite Scrub / Exfoliator: These are fine mineral particles that provide physical exfoliation. They can be added to both oil-based (cold process/hot process) and melt-and-pour soaps.
• CelluScrub™ Max: Made from natural cellulose, these particles also provide physical exfoliation and can be incorporated into solid soaps.

For Acne

Adding specific anti-acne actives to traditional solid soap can be challenging due to the high pH. Many effective anti-acne ingredients are more stable at lower pH levels found in liquid cleansers or leave-on treatments.

• Pep®-Acne (Oligopeptide-10 Anti-microbial Peptide): This peptide is water-soluble and sensitive to heat. While it could potentially be added to melt-and-pour soap at a low temperature, its stability and efficacy in the alkaline soap environment over time are not guaranteed. It's typically used in products with controlled pH.
• QD-365 Anti-Acne Complex: This complex contains several anti-acne ingredients and is water-soluble and heat-sensitive. Similar to Pep®-Acne, it's more suitable for products with controlled pH.
• African Black Soap (Ghana): This is a traditional soap base known for its deep cleansing and acne-fighting properties. While not an additive, using this as your base is an option if you want a soap specifically for acne.

For Wrinkles, Melasma, Freckles, and Skin Whitening

Many ingredients targeting these concerns are also sensitive to pH and heat.

• SclareoWhite™ (Sclareolide, Pure): This ingredient has skin whitening properties and is soluble in oil/glycol/alcohol. It might be possible to incorporate into oil-based or melt-and-pour soap, but its stability in the alkaline environment needs careful consideration and testing.
• GlyciWhite™ (Glycinamide HCL): This whitening ingredient is water-soluble and sensitive to heat above 60°C. It's typically used in lotions or creams with controlled pH, making it difficult to incorporate effectively and stably into solid soap.

General Considerations for Adding Actives to Solid Soap:

• Cold Process Soap: The high pH and heat make it difficult to add many sensitive active ingredients without degradation. Natural additives like herbal powders, clays, or exfoliants are generally more stable.
• Melt-and-Pour Soap: This is easier as you melt a pre-made base and add ingredients. However, the base is still alkaline (though less so than fresh cold process soap). Add sensitive ingredients at the lowest possible temperature just before pouring. Be aware that stability and efficacy might still be compromised compared to other product types.

For many active ingredients targeting specific skin concerns like acne, wrinkles, or hyperpigmentation, you may find better results by using them in leave-on products (serums, creams) or wash-off products with a more skin-friendly pH (like syndet bars or liquid cleansers) rather than traditional solid soap.

If you are making soap for personal use and sale, thorough testing for stability, efficacy, and safety (including pH testing of the final product) is highly recommended when adding new ingredients.