There are a number of reasons why you might want to find a replacement for a raw material you currently using. It could be because the supplier can’t get you the ingredient, you can save money on your formula, the product is no longer stable, or for marketing reasons you want to change. This is probably the motivation for this forum member who wants to find a natural alternative to petrolatum.
If you’re going to switch out a raw material you can do it in the most efficient way by following these 5 steps.
1. Understand what the ingredient does in the formula
If you inherit a formula as most formulators do, there are probably ingredients included for which you are not sure the function. You need to figure this out before you switch for something new. Also, you may think you know the function of the ingredient but it could have multiple functions in your formula. To best figure out the importance of an ingredient for which you want to find a replacement, do a cosmetic knockout experiment, comparing your full formula versus the formula without the target ingredient. This will give you an idea of the performance impact of the ingredient plus the aesthetic impact on the formula.
2. Find potential replacements
Once you know the full impact of the ingredient on your formula you can find potential replacements. The easiest thing to do is to ask your suppliers for their suggested replacements. Certainly, you should get samples of those ingredients. But a single ingredient replacement might not work. You may have to find multiple materials to replace all the functionality of a single ingredient. For example, Guar Hydroxypropyl Trimonium Chloride has both a conditioning effect and some thickening effect. Instead of finding a single ingredient to replace it you could find a new thickener (e.g. Hydroxyethylcellulose) plus a conditioning ingredient (e.g. Polyquaternium 7). Sometimes it’s not a simple replacement.
3. Create prototypes
Once you get your potential ingredients start making your prototypes. Ideally, you can make multiple formulas at the same time using the same ingredients. When you compare replacements you should keep as much the same as possible. Also, be sure to create a control sample so you know how your new formula compares to your current formula. Take special note of any manufacturing changes you have to make to incorporate the new ingredient. This will be important when you write the manufacturing instructions later.
4. Test prototype functionality
After you’ve made the prototypes you’ll want to test them to see if they function the way you want them to. See how they compare to your control formula. Of course, you only need to test the formulas that hold together properly. If they separate or don’t look right either try again or reject that replacement alternative.
The specific tests you run will depend on the type of formula you are making. Foam tests for cleansing products, moisturizing tests for moisturizing products, etc. For all your formulas you should have a standard battery of tests that you routinely conduct and compare your prototypes to those standards.
5. Test prototype stability
Finally, if any of your replacement ingredient prototypes look promising you’ll want to do a stability test to make sure it stays together. Having a great functioning product is great but if it isn’t stable you won’t be able to sell it. I recommend doing functionality tests before stability tests however because there is no point in finding a stable product that doesn’t perform the way you want it. Plus, you can always fix a formula that has stability issues. You can’t improve a functional deficit without having to repeat your stability test. Remember, stability tests should always be the last test you do.
Much of your time as a formulator will be spent finding replacement ingredients either for cost savings reasons, marketing reasons, or just trying to improve your formulas. Following these 5 steps will help make the process more efficient and effective.