Successful product development with Polysorbate 60 (Tween 60) requires more than just adding it to a mixture. To achieve a stable, non-separating emulsion, formulators must follow specific temperature and blending protocols.
This guide covers the technical “how-to” for food, cosmetic, and industrial applications.
1. Preparation: Determining the Dosage
The usage level of Polysorbate 60 varies significantly depending on the application and local regulations (FDA/EFSA).
- Fine Bakery Wares: 0.1% – 0.5% (based on flour weight).
- Whipped Toppings & Oil-based Emulsions: 0.2% – 0.4%.
- Cosmetic Lotions: 1% – 5% (as a primary or co-emulsifier).
- Ice Cream & Frozen Desserts: 0.1% to improve air incorporation and dryness.
2. Temperature and Solubility Rules
Polysorbate 60 is a non-ionic surfactant that becomes more active at specific temperatures:
- Heating: For the best results, heat the water phase to 60°C – 70°C.
- Phase Addition: Polysorbate 60 is typically added to the water phase due to its high HLB (14.9). However, in specific “One-Pot” cosmetic processes, it can be pre-mixed with the oil phase before emulsification.
- Avoid Overheating: Prolonged exposure to temperatures above 90°C may lead to oxidation and off-odors.
3. Step-by-Step Emulsification Process
To create a stable Oil-in-Water (O/W) emulsion using Polysorbate 60, follow these steps:
- Water Phase Preparation: Dissolve Polysorbate 60 in warm water (65°C) while stirring gently to avoid excessive foaming.
- Oil Phase Preparation: Heat your oils/fats to the same temperature as the water phase.
- The Mixing Phase: Slowly add the oil phase into the water phase while using a high-shear mixer.
- Cooling: Continue slow stirring during the cooling process. This ensures the stearic acid chains in Tween 60 crystallize correctly, providing the desired creamy texture.
4. Synergistic Combinations (The HLB System)
In many professional formulations, Polysorbate 60 is not used alone. It is often paired with low-HLB emulsifiers to create a robust “emulsifier system.”
- Tween 60 + Sorbitan Stearate (Span 60): This is the most common B2B pairing. By blending these two, you can “fine-tune” the HLB to perfectly match your specific oil type.
- Tween 60 + Mono- and Diglycerides (GMS): Widely used in industrial cake gels and bread improvers to enhance crumb softness and aeration.
5. Troubleshooting Common Issues
- Product Separation: Usually caused by an incorrect HLB match or insufficient mixing speed. Try adding a small amount of a co-emulsifier.
- Cloudiness in Clear Liquids: Polysorbate 60 may create a cloudy appearance if the concentration is too high. If clarity is required, consider switching to Polysorbate 20.
- Excessive Foaming: Reduce the stirring speed during the initial dissolution in water.
6. Storage and Handling
To maintain the shelf life of your formulation:
- Store Polysorbate 60 in a cool, dry place, away from direct sunlight.
- Ensure the container is tightly sealed to prevent moisture absorption, which can affect the concentration accuracy in your recipes.
