Boiling and Preservation for Formulations with Powders

Regarding your questions:

1. Boiling: Yes, based on the previous response, boiling the mixture of water, Kaolin, and Activated Carbon for 15 minutes is still recommended even with the reduced percentages (8% Kaolin, 0.5% Activated Carbon) and increased Mild Preserved Eco (2%). This step helps to sterilize the raw materials and containers, which is crucial for preventing microbial contamination and achieving a longer shelf life (7 months to 1 year).

2. Preservative Effectiveness: The staff suggested that if boiling is not feasible, a highly effective alternative preservative combination (at maximum allowed rates) is to use 2% Mild Preserved Eco together with 1% Phenonip® P4. This combination is considered highly effective for controlling microbial growth in your formulation.