Recommendations to Prevent Fermentation in Fruit Juice Serum

It is understandable that you are facing fermentation issues with your serum containing fruit juice extract, especially with delayed shipping and high temperatures. Fresh fruit juice contains sugars and nutrients that are ideal for microbial growth, and elevated temperatures accelerate this process.

Your current preservative system, Mild Preserved Eco™ (Benzyl Alcohol, Salicylic Acid, Glycerin, Sorbic Acid) at 1% and PaeoniaPreserve™ at 0.1%, is a good starting point. However, for a challenging formula like this, exposed to high temperatures during transport, you may need to enhance its efficacy.

Here are some strategies you can consider to help inhibit fermentation:

• Adjust the Formula pH: Many preservatives, including Sorbic Acid in Mild Preserved Eco™, work best at a specific pH range, often lower (acidic). Adjusting the serum's pH to a suitable range (typically below 5) can significantly boost the effectiveness of your existing preservative system.
• Add Co-Preservatives or Boosters: Combining different preservatives or using ingredients that enhance preservative activity can provide broader protection against various microbes.
  • Consider adding a system like Phenoxyethanol and Ethylhexylglycerin. This is a widely used and effective combination against bacteria, yeast, and mold. Ethylhexylglycerin also acts as a booster for other preservatives.
  • Sodium Benzoate and Potassium Sorbate are highly effective against yeast and mold, which are common culprits for fermentation in sugary solutions. They work best at low pH (ideally below 5). Adding these in appropriate amounts (e.g., 0.1-0.5% each) can significantly improve control over yeast and mold.
  • Ingredients like Caprylyl Glycol or Hexylene Glycol can act as preservative boosters and solvents, helping to improve the overall efficacy of the preservative system.

Additional Recommendations:

• Ensure Strict Hygiene: Make sure all production processes and equipment are as sterile as possible to minimize the initial microbial load in the product.
• Raw Material Quality: Fresh fruit juice can have a very high initial microbial count. Using fruit extracts that have been sterilized or stabilized might be a better long-term solution.
• Packaging and Shipping: Using airtight packaging and controlling the temperature during shipping are crucial. If possible, consider using temperature-controlled shipping for sensitive products.

By implementing these steps, particularly adjusting pH and adding complementary preservatives or boosters, you can significantly reduce the risk of fermentation in your fruit juice serum during transit.