Cleansing Gel Preservation Issues

Thank you for reaching out regarding the spoilage issue with your natural cleansing gel formulation using Xanthan Gum and Mild Preserve Eco™.

It is common for formulations containing natural ingredients like Xanthan Gum to be more susceptible to microbial growth. Xanthan Gum itself, being a natural polysaccharide, can serve as a nutrient source for microorganisms if not adequately preserved. Mild Preserve Eco™ (Ethylhexylglycerin and 1,3 Propanediol), while a gentle ingredient with some antimicrobial properties, is often used as a booster or co-preservative rather than a standalone broad-spectrum preservative, especially in challenging formulations or at lower concentrations like 1%.

The color change, bad odor, and mold growth you observed are clear indicators of microbial contamination (bacteria, yeast, or mold) in your product. This suggests that the preservation system at 1% Mild Preserve Eco™ was not sufficient to protect your specific formulation over time.

To effectively preserve your natural cleansing gel and prevent spoilage, you should consider using a broad-spectrum preservative system that is more robust. Here are a few alternatives that are suitable for cosmetic formulations and can provide better protection:

• NaturePreserve™ Ultra (Gluconolactone & Sodium Benzoate): This is a natural broad-spectrum preservative effective against bacteria, fungi, and yeast. It works best in a pH range of 3-6. The recommended usage rate is 0.75-2.0%, with 1.25% being a general recommendation.
• Global Guard™ 221 (Dehydroacetic Acid & Benzyl Alcohol & Water): Another natural broad-spectrum option effective in a pH range of 2-7. The recommended usage rate is 0.5-1.1%.
• Preserve-BSB™ (Benzyl Alcohol, Sodium Benzoate, Potassium Sorbate, Aqua): This broad-spectrum preservative is effective against bacteria, mold, and yeast and works up to a pH of 5.5. The recommended usage rate is 0.3-1.0%.
• Coco-Preserve™ (Cocos Nucifera (Coconut) Fruit Extract, 1,2-Hexanediol, Butylene Glycol): A natural preservative derived from coconut extract, offering broad-spectrum activity against bacteria, yeast, and mold. It is effective in a pH range of 4-8. The recommended usage rate is 1-2%.
• Mild Preserved™ COS (Phenoxyethanol, Chlorphenesin, Caprylyl Glycol): While not natural origin, this is a highly effective broad-spectrum preservative that works in a wide pH range of 2-8 and is odorless. The recommended usage rate is 0.75-1.5%. This could be an option if natural origin is not the absolute highest priority.

When choosing a preservative, consider the target pH range of your final cleansing gel formulation, as preservatives are only effective within specific pH limits. You may need to adjust the pH of your formula to ensure the chosen preservative works optimally.

Using a natural thickener like Xanthan Gum does increase the microbial challenge, but it does not mean you cannot use it. It simply means you need a sufficiently strong and appropriate preservative system to counteract this. Increasing the concentration of Mild Preserve Eco™ to 1.5-2.0% might offer better protection, but switching to a different broad-spectrum preservative designed for more challenging formulations is often a more reliable solution.

Important: Regardless of the preservative chosen, it is highly recommended to perform a challenge test on your final formulation before producing and distributing it. A challenge test will confirm that your chosen preservative system is effective at preventing microbial growth in your specific product over its intended shelf life under realistic conditions.

We recommend selecting one of the suggested broad-spectrum preservatives and incorporating it at the recommended usage rate, ensuring the pH of your formulation is within the effective range of the chosen preservative. This should provide much better protection against spoilage compared to using 1% Mild Preserve Eco™ alone in a natural gel base.