Troubleshooting Serum Formulation: Emulsification and Separation Issues with High Water Content

Question

I am trying to make a serum formulation using Silky Serum Base Plus. My formula has a relatively high water content, including ingredients like Pitera and Niacinamide. I attempted to mix the oil phase and water phase using a blender attached to a drill for half an hour, but the mixture did not emulsify and remained separated.

Based on the recommendation to increase Silky Serum Base Plus to 15% (from an initial lower percentage), could you please explain:

Why is it necessary to increase the percentage of Silky Serum Base Plus in a formula with high water content?
What is the correct mixing procedure for this type of serum formulation, especially regarding the use of a high-speed blender and the addition of the water phase?
What might have caused my previous mixing attempt to fail despite using a blender for an extended period?

MySkinRecipes Expert · Accepted Answer

Subject: Re: Inquiry about Mixing Method

Hello,

Thank you for providing the details of your mixing attempt. It sounds frustrating when the ingredients don't emulsify as expected.

Based on the staff's advice and your experience, here are the key points and steps for mixing this formula:

Important Note: As the staff mentioned, this formula, especially with Silky Serum Base Plus, requires a high-speed blender (at least 1000 rpm) for proper emulsification. Manual mixing will not work.

Mixing Steps:

Prepare the Oil Phase: Blend the ingredients listed under "ส่วนของน้ำมัน" (Oil Phase) together until well combined. The staff suggested increasing Silky Serum Base Plus to 15% and reducing water by 5% to help with emulsification due to the high water content.
Prepare the Water Phase: Blend the ingredients listed under "ส่วนของน้ำ" (Water Phase) together. Note that the Phospholipid will likely make this phase creamy.
Combine Phases: While continuously blending the Oil Phase at high speed, slowly add the Water Phase in very small increments. Allow each addition to fully incorporate before adding more.
Continue Blending: Keep blending until the entire Water Phase has been added and the mixture is uniform and thickens into a stable serum texture.
Add Preservative: Once the serum is fully emulsified, add the Mild Preserve Eco and blend until it is evenly distributed.

Why Increase Silky Serum Base Plus?

The staff recommended increasing Silky Serum Base Plus from 10% to 15% because your formula has a relatively high water content (originally 42.5%, even with other water-soluble ingredients like Pitera, Niacinamide, etc.). A high water-to-oil ratio can make it difficult to form a stable emulsion, especially if the final serum is intended to be thick. Increasing the emulsifier (Silky Serum Base Plus) helps to better bind the oil and water phases together and prevent separation.

Troubleshooting:

Since you mentioned trying with a blender attached to a drill for half an hour without success, consider these points:

Blender Speed: Is the blender truly reaching at least 1000 rpm? Some drill attachments might not provide sufficient speed or shear force.
Adding Speed: Were you adding the water phase very slowly, drop by drop or in tiny streams, allowing full incorporation each time? Adding too quickly is a common cause of emulsion failure.
Blending Time: While you blended for a long time, was it continuous high-speed blending while adding the water phase and after the addition was complete to ensure stability?

If you can describe your blending setup (type of head, drill speed setting if known) and exactly how you added the water phase (how fast, how much at a time), the staff might be able to provide more specific advice.

I hope these detailed steps help you succeed with your formulation!