Preservative Selection for Sodium Laureth Sulfate (SLES) Shampoo

For a shampoo formulated with Sodium Laureth Sulfate (SLES), you need a broad-spectrum preservative that is stable in the presence of anionic surfactants and effective within the typical pH range of hair care products (usually pH 5.0–7.0).

Recommended Preservatives

1. K940 Preservative: This is a highly effective, broad-spectrum synthetic preservative blend. It is widely used in rinse-off products like shampoos because it is stable, easy to incorporate, and provides strong protection against bacteria, yeast, and mold.
2. Preserve-BSB™: If you are looking for a more "natural-compliant" option (ECOCERT/COSMOS approved), this blend is an excellent choice. It works best in formulations with a pH below 5.5. It is water-soluble and integrates well into surfactant systems.
3. Potassium Sorbate: Often used as a co-preservative to boost protection against mold and yeast. It must be used in acidic conditions (pH below 5.5) to be active.

Formulation Tips for SLES Shampoo

• pH Control: Most preservatives are pH-dependent. Ensure your shampoo's final pH is adjusted (usually with Citric Acid) to the range required by your chosen preservative.
• Addition Point: Most preservatives should be added during the "cool-down" phase (below 40°C) to ensure stability, though some can withstand higher temperatures.
• Compatibility: SLES is an anionic surfactant. All the preservatives mentioned above are compatible with anionic systems.

You can explore more ingredients for your formulation in the Cosmetics > Hair Care > Shampoo category.