Preservative Usage in Gel Cleanser and Oil-Free Lotion Spray

Regarding your question about using 1% Mild Preservative Eco in your gel cleanser and oil-free lotion spray formulas, here is some guidance:

• Mild Preservative Eco Usage Rate: The recommended usage rate for Mild Preservative Eco in general cosmetic formulas is typically 1.0-1.5%. Using 1% is within this general range.

• Considerations for Natural Ingredients: Both of your formulas contain hydrosols (Lavender hydrosol and Chamomile hydrosol), which are natural ingredients. Formulas with a high percentage of natural ingredients can sometimes be more susceptible to microbial growth. While 1% is acceptable, using 1.5% Mild Preservative Eco might provide more robust preservation, especially for a beginner formulation.

• pH Compatibility: Mild Preservative Eco is effective in formulas with a pH range of 4-9. In your gel cleanser formula, Coco Glucoside has a naturally high pH (around 11.5) and requires pH adjustment. It is important to check the final pH of both your gel cleanser and lotion spray after adding all ingredients and adjust it if necessary to ensure it falls within the effective range of the preservative.

• Challenge Testing: If you plan to produce these formulas for sale, it is highly recommended to perform a challenge test to confirm the effectiveness of the preservative system in your specific formulation.

In summary, 1% Mild Preservative Eco is within the standard usage range, but you may consider increasing it to 1.5% for added protection, particularly due to the presence of natural hydrosols. Always check and adjust the final pH of your formulas for optimal preservative performance.