Serum Bead Formulation Issues: Separation and Texture

Question

Hello, first, here is the formula:

serum bead

water phase
[url=https://www.myskinrecipes.com/shop/%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B8%AA%E0%B8%A3%E0%B9%89%E0%B8%B2%E0%B8%87%E0%B9%80%E0%B8%99%E0%B8%B7%E0%B9%89%E0%B8%AD%E0%B9%80%E0%B8%88%E0%B8%A5-%E0%B8%99%E0%B9%89%E0%B8%B3-water-gellant/8615-iota-carrageenan.html:3d9ocjyg]Iota Carrageenan[/url:3d9ocjyg] 0.2%
[url=http://www.myskinrecipes.com/shop/%E0%B8%AA%E0%B8%A3%E0%B9%89%E0%B8%B2%E0%B8%87%E0%B9%80%E0%B8%99%E0%B8%B7%E0%B9%89%E0%B8%AD%E0%B9%80%E0%B8%88%E0%B8%A5-thickener/895-sodium-alginate-%E0%B9%80%E0%B8%88%E0%B8%A5%E0%B8%A1%E0%B8%B2%E0%B8%AA%E0%B9%8C%E0%B8%81.html:3d9ocjyg]sodium alginate[/url:3d9ocjyg] (Algin, Super Fine) 0.3%
1,3-[url=http://www.myskinrecipes.com/shop/%E0%B8%AA%E0%B9%88%E0%B8%A7%E0%B8%99%E0%B8%9B%E0%B8%A3%E0%B8%B0%E0%B8%81%E0%B8%AD%E0%B8%9A%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B8%AA%E0%B8%B3%E0%B8%AD%E0%B8%B2%E0%B8%87%E0%B8%84%E0%B9%8C/1337-1-3-propanediol.html:3d9ocjyg]Propanediol[/url:3d9ocjyg] (Natural) 3%
[url=http://www.myskinrecipes.com/shop/%E0%B8%A1%E0%B8%AD%E0%B8%A2%E0%B8%8B%E0%B9%8C%E0%B9%80%E0%B8%88%E0%B8%AD%E0%B8%A3%E0%B9%8C/197-trehalose-%E0%B8%97%E0%B8%A3%E0%B8%B5%E0%B8%AE%E0%B8%B2%E0%B9%82%E0%B8%A5%E0%B8%AA.html:3d9ocjyg]TreMoisture™ (Trehalose)[/url:3d9ocjyg] 2%

oil phase
[url=http://www.myskinrecipes.com/shop/emollient-ester-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B9%80%E0%B8%9E%E0%B8%B4%E0%B9%88%E0%B8%A1%E0%B8%84%E0%B8%A7%E0%B8%A1%E0%B8%99%E0%B8%B8%E0%B9%88%E0%B8%A1%E0%B8%A5%E0%B8%B7%E0%B9%88%E0%B8%99/1310-pentaerythrityl-tetraisostearate.html:3d9ocjyg]Pentaerythrityl Distearate[/url:3d9ocjyg] 2%
[url=https://www.myskinrecipes.com/shop/emollient-ester-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B9%80%E0%B8%9E%E0%B8%B4%E0%B9%88%E0%B8%A1%E0%B8%84%E0%B8%A7%E0%B8%B2%E0%B8%A1%E0%B8%99%E0%B8%B8%E0%B9%88%E0%B8%A1%E0%B8%A5%E0%B8%B7%E0%B9%88%E0%B8%99/1318-stearic-acid.html:3d9ocjyg]Stearic Acid[/url:3d9ocjyg] 2%
[url=http://www.myskinrecipes.com/shop/%E0%B8%99%E0%B9%89%E0%B8%B3%E0%B8%A1%E0%B8%B1%E0%B8%99%E0%B8%AA%E0%B8%81%E0%B8%B1%E0%B8%94%E0%B8%98%E0%B8%A3%E0%B8%A1%E0%B8%8A%E0%B8%B2%E0%B8%95%E0%B8%B4/85-extra-virgin-olive-oil-%E0%B8%99%E0%B9%89%E0%B8%B3%E0%B8%A1%E0%B8%B1%E0%B8%99%E0%B8%A1%E0%B8%B0%E0%B8%81%E0%B8%AD%E0%B8%81-%E0%B8%9A%E0%B8%A3%E0%B8%B4%E0%B8%AA%E0%B8%B8%E0%B8%97%E0%B8%98%E0%B8%B4%E0%B9%8C.html:3d9ocjyg]Olive Oil (Extra Virgin)[/url:3d9ocjyg] 5%
[url=https://www.myskinrecipes.com/shop/oil-in-water-high-hlb/6371-polyglyceryl-10-oleate-.html:3d9ocjyg]Polyglyceryl-10 Oleate[/url:3d9ocjyg] 2%
[url=http://www.myskinrecipes.com/shop/%E0%B8%AA%E0%B9%88%E0%B8%A7%E0%B8%99%E0%B8%9B%E0%B8%A3%E0%B8%B0%E0%B8%81%E0%B8%AD%E0%B8%9A%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B8%AA%E0%B8%B3%E0%B8%AD%E0%B8%B2%E0%B8%87%E0%B8%84%E0%B9%8C/140-laureth-23-emulsifier-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B8%9B%E0%B8%A3%E0%B8%B0%E0%B8%AA%E0%B8%B2%E0%B8%99%E0%B9%80%E0%B8%99%E0%B8%B7%E0%B9%89%E0%B8%AD%E0%B8%84%E0%B8%A3%E0%B8%B5%E0%B8%A1-%E0%B8%8A%E0%B8%99%E0%B8%B4%E0%B8%94%E0%B9%81%E0%B8%82%E0%B9%87%E0%B8%87-%E0%B9%83%E0%B8%8A%E0%B9%89%E0%B8%87%E0%B8%B2%E0%B8%99%E0%B9%88%E0%B8%B2%E0%B8%A2.html:3d9ocjyg]Laureth-23[/url:3d9ocjyg] 3%
[url=http://www.myskinrecipes.com/shop/%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B8%81%E0%B8%B1%E0%B8%99%E0%B9%80%E0%B8%AA%E0%B8%B5%E0%B8%A2/155-phenoxyethanol-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B8%81%E0%B8%B1%E0%B8%99%E0%B9%80%E0%B8%AA%E0%B8%B5%E0%B8%A2-%E0%B9%84%E0%B8%A1%E0%B9%88%E0%B8%A1%E0%B8%B5paraben.html:3d9ocjyg]Phenoxyethanol[/url:3d9ocjyg] (Extra Pure) 1%
[url=http://www.myskinrecipes.com/shop/mica-pearl-%E0%B8%9C%E0%B8%87%E0%B8%A1%E0%B8%B8%E0%B8%81/604-gold-glitter-mica.html:3d9ocjyg]Gold Glitter Mica ประกายทอง (ขนาด C)[/url:3d9ocjyg] 0.2%
DI q.s.100

Based on the formula I made, the serum separated after being left for several days. I want to know if this is related to the [url=http://www.myskinrecipes.com/shop/36-emulsifier:3d9ocjyg]Emulsifier[/url:3d9ocjyg]? Which one should be adjusted or changed?

Another question is, after making it, the texture feels quite heavy. Can I reduce the oil content to make it lighter? Thank you very much.

MySkinRecipes Expert · Accepted Answer

Re: Inquiry about Serum Bead Formula

Hello,

Thank you for providing your serum bead formula and describing the issues you encountered.

You mentioned that the serum separates after a few days and asked if this is related to the emulsifier. Yes, phase separation in an emulsion is often caused by an unstable emulsifier system. Your formula uses Polyglyceryl-10 Oleate and Laureth-23 as O/W emulsifiers. While these are effective emulsifiers, their combination and concentration might not be optimal for long-term stability with your specific oil phase composition (including Olive Oil, Pentaerythrityl Tetraisostearate, and Stearic Acid) and the presence of gelling agents (Iota Carrageenan, Sodium Alginate) in the water phase.

To improve stability and prevent separation, you could consider:

Reviewing your process: Ensure the gelling agents are fully hydrated and the oil phase is properly heated (if necessary) before emulsification. Ensure adequate mixing/shear during the emulsification step.
Adjusting the emulsifier system: You might need to adjust the ratio or total concentration of Polyglyceryl-10 Oleate and Laureth-23. Alternatively, consider using a different emulsifier or a blend known for better stability in systems with natural oils and gelling agents. Examples of emulsifier types to explore include combinations of high and low HLB emulsifiers, or specific proprietary blends designed for challenging formulations.
Checking ingredient compatibility: While less common, ensure all ingredients are compatible.

Regarding your second question about the texture being too heavy and wanting to reduce the oil phase:

Yes, the oil phase (Olive Oil, Pentaerythrityl Tetraisostearate, Stearic Acid) contributes significantly to the richness and perceived heaviness of the serum. You can definitely reduce the amount of oil to achieve a lighter texture.

However, when you reduce the oil phase, you may also need to adjust the emulsifier concentration or ratio to maintain a stable emulsion. Reducing the internal (oil) phase can sometimes make emulsification easier, but the emulsifier system still needs to be balanced for the new oil load.

Suggestions for reducing oil:

Start by gradually reducing the percentage of Olive Oil, as it is the largest component of your oil phase.
After reducing the oil, observe the stability. If separation still occurs, you may need to revisit the emulsifier system as discussed above.
Reducing the oil phase will make the gel structure from Carrageenan and Alginate more prominent in the final texture.

Formulation development often involves iteration and testing. Making small adjustments and observing the results is key.

I hope this helps!

Best regards,
[Your Name/AI Identifier]