Mixing Actives into Absolue Soft Cream Base: Viscosity, Stability, and Preservation
Question
I have purchased Absolue Soft Cream Base and plan to mix it with other ingredients, specifically [active ingredients in water] or [active ingredients in oil].
I previously saw a question about the maximum amount of [active ingredients in water] that could be added to Absolue Soft Cream Base, and the staff replied that 10% is acceptable.
I have the following questions:
1. If I add [active ingredients in water] at a proportion of 20% (20 parts active ingredients in water : 80 parts Absolue Soft Cream Base), would the cream's viscosity change too much? Would it become loose like a lotion, or would it still retain a cream consistency?
2. If I add [active ingredients in oil] at a proportion of 20% (20 parts active ingredients in oil : 80 parts Absolue Soft Cream Base), would the cream's viscosity change too much? Would it become too sticky, or would the texture still be acceptable as a cream?
3. If I add either [active ingredients in water] or [active ingredients in oil] at a proportion of 20%, would this affect the preservative ability of the base cream? What is the maximum proportion of active ingredients that can be added without compromising the preservative ability of the base cream?
Answer
Information about Absolue Soft Cream Base
Thank you for your question regarding Absolue Soft Cream Base. Based on the product information, this base is recommended for use at 90-100%. Adding ingredients at 20% means the base will be at 80%, which is outside the recommended usage range.
Here are the answers to your specific questions:
- Adding 20% [active ingredients in water]: Adding 20% water-based active ingredients is a significant amount and is outside the recommended usage rate for the base. It is highly likely that adding this much water will significantly decrease the viscosity of the cream, potentially making it much thinner, possibly like a lotion, and could affect the stability of the emulsion.
- Adding 20% [active ingredients in oil]: Similarly, adding 20% oil-based active ingredients is outside the recommended usage rate. Adding a large amount of oil can also disrupt the cream's structure and decrease viscosity. The resulting texture (e.g., stickiness) will depend heavily on the specific oil-based active ingredient used.
- Effect on preservative ability: The product description states that Absolue Soft Cream Base is Preservative-Free. This means the base itself does not contain a preservative system to protect the final product from microbial growth, especially after adding other ingredients. Adding 20% of any active ingredient (water or oil) will introduce potential contaminants and dilute the base. To ensure the stability and safety of your final product, you must add a suitable broad-spectrum preservative system to your formulation when adding active ingredients. The maximum proportion you can add without affecting preservative ability is essentially zero, as the base provides no preservation; preservation must come from added ingredients.
In summary, adding 20% of either water-based or oil-based actives is likely to significantly change the viscosity and potentially the stability of the cream base, as it falls outside the recommended usage range. Crucially, since the base is Preservative-Free, you will need to add a separate preservative system to your final formulation regardless of the amount of active ingredients added, to prevent microbial contamination.
