Allantoin Solubility and Mixing Procedure in Shower Gel/Shampoo Formula
Question
I understand that Allantoin has a solubility of approximately 0.5% in water, meaning in a formula with 50% water, the expected amount that can dissolve is around 0.25% of the total formula.
My formula is a Shower Gel/Shampoo containing:
EasyThickGlycerinPanthenol(powder)Natural Betaine- Other liquid ingredients
Given that Glycerin and Natural Betaine can help increase Allantoin's solubility, is it possible to use Allantoin at a higher concentration of 0.4-0.5% in this specific formula? If so, what is the optimal mixing procedure to ensure Allantoin and Natural Betaine dissolve completely, especially considering the presence of EasyThick and other ingredients?
Answer
Hello!
Regarding the dissolution of Allantoin in your formula containing EasyThick, Glycerin, and Panthenol (powder), among other liquid ingredients (for Shower Gel/Shampoo):
Based on the previous discussion and calculation, Allantoin's solubility in water is approximately 0.5%. Therefore, in a formula with approximately 50% water, the maximum amount of Allantoin expected to dissolve in the water phase is about 0.25% of the total formula.
It is correct that your formula contains Glycerin and Natural Betaine, as both ingredients have properties that help increase the solubility of Allantoin.
Regarding your question about using Allantoin at 0.4-0.5% of the formula, this amount is higher than the 0.25% calculated based solely on the water content. However, due to the properties of Glycerin and Natural Betaine which help increase solubility, it may be possible for Allantoin to dissolve at a higher amount in your specific formula. The recommendation is to test this in a small batch first to ensure that the Allantoin dissolves completely and does not recrystallize when the mixture cools down or over time. If you find that some remains undissolved, you should reduce the amount of Allantoin.
For the optimal procedure to dissolve Allantoin and Natural Betaine effectively in a formula containing EasyThick, Glycerin, Panthenol (powder), and other ingredients (for Shower Gel/Shampoo), I recommend the following steps:
- Prepare the water phase: Combine water, EDTA, Glycerin, Natural Betaine, and Allantoin in a heat-resistant container.
- Heat and Dissolve: Gently heat the mixture from step 1 while stirring continuously. Higher temperature will help Allantoin and Natural Betaine dissolve more easily and quickly. Stir until both ingredients are completely dissolved and the water is clear.
- Add EasyThick: Once Allantoin and Natural Betaine are fully dissolved, while the mixture is still warm, gradually add EasyThick. Stir or use a mixer (if available) to help EasyThick disperse and dissolve well in the water. Continue stirring until EasyThick is completely dissolved and the mixture starts to form a gel.
- Cool Down: Stop heating and let the mixture from step 3 cool down to room temperature or below.
- Add Remaining Ingredients: Once the mixture has cooled, add Panthenol (powder) and other ingredients that are sensitive to heat or do not require high heat, such as surfactants, preservatives, fragrance, colorants, etc. Stir or mix gently until everything is uniformly combined.
Reason for this recommended order: Dissolving Allantoin and Natural Betaine in the warm, less viscous water phase (before adding EasyThick) with the help of solubility aids like Glycerin will ensure maximum dissolution efficiency. Once Allantoin and Betaine are dissolved, adding EasyThick to the still-warm mixture will help it hydrate and thicken properly. Then, heat-sensitive ingredients are added in the final cooling phase.
I hope this advice is helpful. Please feel free to ask if you have any further questions.
