Choosing a Preservative for Tamarind and Coffee Scrubs

For tamarind and coffee scrubs, which contain natural ingredients and are likely to have a low pH, selecting a broad-spectrum preservative that is effective in acidic conditions is important to prevent microbial growth (bacteria, yeast, and mold).

You are considering Mild Preserved™ and NaturePreserve™ products. Based on the product information, here's a comparison of relevant options:

• NaturePreserve™ Ultra: This is a natural preservative effective against bacteria, fungi, and yeast. It works in a pH range of 3-6. It is added to the water phase and is heat tolerant. It is acidic and may lower the formula's pH. Do not use with Vitamin C (L-Ascorbic Acid).
• NaturePreserve™ LB2: Another natural option, this preservative is highly effective against bacteria and fungi at low pH values (range 2.0-6.5). It is a broad-spectrum preservative soluble in water. Avoid heat above 50°C.
• Mild Preserved™ COS: This is a synthetic broad-spectrum preservative that is water-soluble and effective over a wide pH range of 2-8. It is odorless and should be added below 45°C.
• Mild Preserved Eco™ and Mild Preserved SC10™ (and likely Mild Preserved CGZ™): These are marketed as "preservative-free" ingredients that help prevent microbial growth. Mild Preserved Eco™ and CGZ™ work in a pH range of 4-9, while Mild Preserved SC10™ works up to pH 12. While gentle, they might be less robust for formulas with high natural content and potential contamination compared to dedicated broad-spectrum preservatives, especially if the pH is below 4 for Eco/CGZ.

Recommendation:

Given that tamarind is acidic, your scrub's pH will likely be low. Therefore, preservatives that are effective in acidic environments are preferred.

• If you prefer a natural preservative and your scrub's pH is between 2.0 and 6.5, NaturePreserve™ LB2 is a strong candidate.
• If you prefer a natural preservative and your scrub's pH is between 3 and 6, NaturePreserve™ Ultra is also suitable.
• If you are open to a synthetic preservative and need a wide pH range (2-8), Mild Preserved™ COS is a reliable option.

It is crucial to measure the pH of your final scrub formulation to confirm which preservative is most suitable based on its effective pH range. Always use the preservative at the recommended usage rate.

Regardless of the preservative chosen, it is highly recommended to perform a challenge test on your finished product to ensure the preservative system is effective against microbial contamination in your specific formula before selling or distributing it.