Boswellia Serrata Extract Solubility and Cream Stability Issues

Question

I am formulating a cream and encountered issues with adding Boswellia Serrata Extract. The product instructions state to dissolve in Propylene Glycol and add in the final step, avoiding heat, with a recommended pH of 4.0-6.5.

Does warming the mixture to aid dissolution reduce the efficacy of Boswellia Serrata Extract?

I followed steps 1-4 to get a good cream texture. However, when adding step 5 (which contains Boswellia Serrata Extract dissolved in 1,2-Hexanediol, even increasing 1,2-Hexanediol to 6% did not fully dissolve the Boswellia), the cream became liquid and the texture seemed inconsistent. I tried adding double the amount of Luxury Cream Maker and double the amount of water, which helped the texture become more consistent but it's still not as good as before, and I suspect it might separate over time. What is the reason for this problem?

MySkinRecipes Expert · Accepted Answer

Based on the conversation, the issues you encountered are related to the solubility of Boswellia Serrata Extract in 1,2-Hexanediol and the stability of your cream formulation when adding the mixture.

Solubility:

Complete dissolution of Boswellia Serrata Extract is necessary.
Boswellia Serrata Extract is less soluble in 1,2-Hexanediol compared to Propylene Glycol. Even using 6% 1,2-Hexanediol for 0.5% Boswellia might not be sufficient.
Gentle warming (50-60°C) can assist dissolution, though prolonged heat might slightly impact efficacy. Adding other solvents like Propylene Glycol or Butylene Glycol is another option to improve solubility without heat.

Formulation Stability:

The cream became liquid and unstable because the high amount of 1,2-Hexanediol in phase 5 acts as an oil phase, and the total oil phase in your formula exceeded the capacity of the Luxury Cream Maker emulsifier (which supports approximately 20% oil).
Adding more water is not the correct solution for this type of instability.

Recommended Solutions:

Adjust Emulsifier: Increase the amount of Luxury Cream Maker or switch to a stronger emulsifier like Satin Cream Maker that can handle a higher oil load.
Use Stabilizers: Incorporate cream stabilizers such as ClayThick or ClayThick Ready.
Reduce Boswellia/Solvent: The most cost-effective approach recommended is to reduce the concentration of Boswellia Serrata Extract (e.g., to 0.25%) and use a lower percentage of 1,2-Hexanediol (e.g., 3%). This makes the mixture easier to dissolve and the overall formulation more stable, even if it slightly reduces the Boswellia concentration.