Foot Spray Formulation Advice

Based on your proposed formula for a foot spray:

• Anti-Sweat™ (Aluminum Chlorohydrate) 15%
• Odor-Kill™ (water-soluble) 1%
• DeoMax™ Liquid 1%
• Mild Preserve Eco 1%
• Water to 100%

Here are the answers to your questions:

1. Mixing Method

Simply shaking the ingredients together may not be sufficient.

• Anti-Sweat™ is a powder that needs to dissolve in water. At 15%, it requires proper blending or stirring to ensure it fully dissolves and disperses evenly. It might appear cloudy initially and could take up to 24 hours to become clear.
• Odor-Kill™ is also a powder that needs to be blended until dissolved in the water phase. Avoid heating it above 50°C.
• Mild Preserve Eco dissolves in water but benefits from blending for about 5 minutes to achieve clarity.

For best results, it is recommended to blend or stir the ingredients thoroughly rather than just shaking. A suggested mixing order would be to dissolve Anti-Sweat™ in the water first, then add DeoMax™ Liquid and Mild Preserve Eco (blending well), and finally add Odor-Kill™ (blending gently, avoiding heat).

2. Effectiveness and Adjustments

This formula includes ingredients that address both sweat and odor, so it has good potential to be effective for foot odor.

• Anti-Sweat™ helps reduce sweating, which is a major cause of odor.
• Odor-Kill™ and DeoMax™ Liquid are deodorizers that help neutralize or absorb existing odors.
• Mild Preserve Eco provides preservation and also has antibacterial properties that help control odor-causing bacteria.

The concentrations you've chosen are within the recommended ranges for these ingredients.

Potential adjustments for optimization:

• pH Level: Aluminum Chlorohydrate works best in a slightly acidic environment, typically pH 4-6. It's advisable to check the pH of your final mixture and adjust it if necessary to be within this range.
• Stability: Consider adding 0.1-0.2% Disodium EDTA to the water phase. This can help improve the stability and clarity of formulas containing Aluminum Chlorohydrate.
• Feel: Your formula uses a high percentage of water relative to Anti-Sweat™. This might result in a product that feels wet on the skin compared to formulations with less water or those based on alcohol or silicones, which are designed for a drier feel.

Overall, the formula should be effective, but checking and adjusting the pH and adding Disodium EDTA can enhance its performance and stability.

3. Shelf Life

The shelf life of the finished product depends on several factors, including the ingredients used, the effectiveness of the preservative system, and storage conditions.

Your formula includes Mild Preserve Eco at a suitable concentration (1%) for a deodorant product, which acts as a preservative to prevent microbial growth.

Given the ingredients and the presence of a preservative, you can generally expect a shelf life of at least 6 months to 1 year when stored properly.

For optimal longevity, especially considering the recommendation for DeoMax™ Liquid, storing the finished spray in a cool place, away from direct sunlight and heat (refrigeration is ideal if possible), will help maintain its quality and effectiveness over time.

For commercial products, a formal challenge test is necessary to determine the precise shelf life and ensure the preservative system is fully effective.