First things first—learn about it. If the ingredient is in the Humblebee & Me DIY Encyclopedia, you should find all the information you need to incorporate it there. Your supplier should also be able to provide you with all this information. Otherwise, start googling! Here’s a list of things you should know, though there may be other things depending on the ingredient:
- What is it soluble in? Once you know this, you know your formula will need to contain some of whatever the ingredient is soluble in so it will dissolve/be compatible. If your ingredient is something like a carrier oil, your recipe will need to be anhydrous or an emulsion. If your ingredient is something water-soluble, like panthenol, your recipe will need some water—be it mostly water or an emulsion.
- What is the recommended usage rate? Now you know how much to use. This is typically a range, with a minimum and maximum percentage.
- Is it heat sensitive? If yes, don’t heat it past that maximum heat level (typically 40–45°C)
- What is its pH? Is it compatible with your product?
- Does it need a certain pH to work? Does that pH work with the rest of the ingredients in your product?
- What is its charge? Is it compatible with your product?
- Is there anything the ingredient explicitly cannot be used with? Don’t do that, basically.
Once you have answers to all of these questions you’ll know 1) how much to use and 2) which phase to put it into. That should be about it!
Make sure you are removing the percentage of the new ingredient from (generally speaking) either the water or the most prominent oil in your product to keep the recipe in balance. Which phase you remove from depends on the solubility of the ingredient. Water soluble ingredients will deduct from the water phase, oil soluble ingredients will deduct from the oil phase.
Posted in: Troubleshooting & Adjusting