Improving Flowability and Reducing Odor in Cooling Body Powder Formulation
Question
I am formulating a cooling body powder (100g batch) using rice talc as the base, but the resulting powder has poor flowability due to clumping after incorporating liquid components.
The initial formulation details are:
- Rice Talc Base: 86.7 g
- Anti-caking silica: 5 g
- Menthol crystals: 5 g (pre-dissolved in 75% Alcohol 1 g)
- Fragrance: 3 g
- Thymol: 0.3 g
The mixing process involves dry blending the talc and silica first, then adding the liquid solution (menthol/alcohol), fragrance, and thymol, leading to clumping, followed by grinding and blending in a household blender.
How can I modify the formulation and/or mixing procedure to significantly improve the powder's flowability while maintaining a strong cooling sensation and minimizing the overall strong odor? (Note: Previous trials with liquid menthol resulted in a stronger odor and weaker cooling effect compared to menthol crystals or Long-Cool.)
Answer
The primary issue of poor powder flowability stems from the high amount of liquid ingredients (alcohol and fragrance, totaling 4g or 4% of the formula) added to the powder base. This causes clumping and increased relative humidity, even after grinding.
To resolve the flow issue, maintain the cooling effect, and minimize the strong odor, we recommend adjusting the formula and mixing procedure as follows:
1. Key Recommendations
| Problem | Solution | Product Recommendation |
|---|---|---|
| Poor Flow (Clumping) | Reduce total liquid content and use a Liquid Pre-mix technique. | Anti-caking Silica (ID 6853) for absorption. |
| Strong Odor & Cooling | Replace volatile Menthol/Alcohol solution with an encapsulated powder. | Long-Cool™ (Encapsulated Menthol) (ID 10993). |
2. Recommended Revised Formula (100g Batch)
| Ingredient | Original Amount (g) | Recommended Amount (g) | Role |
|---|---|---|---|
| Rice Talc Base | 86.7 | 90.7 | Powder Base |
| Anti-caking Silica (ID 6853) | 5.0 | 6.0 | Flow Agent, Liquid Absorption |
| Long-Cool™ (ID 10993) | 0.0 | 2.0 | Powder Cooling Agent (Replaces Menthol/Alcohol) |
| Menthol Crystals | 5.0 | 0.0 | Replaced |
| 75% Alcohol | 1.0 | 0.0 | Eliminated |
| Fragrance | 3.0 | 1.0 | Reduced to minimize liquid and odor |
| Thymol | 0.3 | 0.3 or 0.0 | Consider removal for odor reduction |
| Total | 100.0 | 100.0 |
Note: If Thymol (0.3g) is retained, reduce the Rice Talc Base to 90.4g.
3. Improved Mixing Procedure (Crucial for Flow)
The correct mixing procedure is vital for achieving good flow when incorporating liquid ingredients into powders.
- Dry Blend Preparation: Combine the Rice Talc Base (90.7g), Long-Cool™ (2.0g), and Anti-caking Silica Part 1 (3.0g). Blend thoroughly.
- Liquid Pre-mix Preparation: In a separate container, mix the Fragrance (1.0g) with Anti-caking Silica Part 2 (3.0g). Mix until the silica has fully absorbed the fragrance and the mixture appears to be a uniform, dry powder.
- Final Blend: Gradually add the absorbed liquid pre-mix (from step 2) into the dry blend (from step 1). Blend/grind further until the powder is fine and exhibits good flowability.
Using the Liquid Pre-mix technique with silica ensures the liquid is encapsulated and evenly distributed, preventing clumping and significantly improving powder flow.
Related Products Mentioned
Anti-Caking Silica
