We had an interesting question posed by one of our readers who has a background in Chemical Engineering. Specifically, he wanted to know if there were some general guidelines for scaling up a formulation and creating a manufacturing procedure. Since we’ve never written specifically about this in the past, here are eight tips that can make your scale up from the lab to the production plant easier. While none of these tips will apply to every formula they are a good guideline to help you craft your manufacturing procedures.
1. Start with abundance
When making a batch you should fill the tank up with the ingredient that is the most abundant in the formulation. Since the vast majority of formulations are water-based, this typically means you fill the tank first with water.
2. Put in your powders
Since many water soluble powders can take a long time to disperse or dissolve, it is best that you get those ingredients mixing. This will speed things up considerably. You also don’t have to necessarily wait until every bit of the powder is evenly mixed into the formula before adding more ingredients on top.
3. Heat helps (usually)
Even if a formulation doesn’t need to be heated to melt the ingredients, it is often helpful to heat up the batch a bit to speed things up. In general, warmer ingredients take less time to blend. Note that this is not always the case. In fact, cellulose raw materials often go into solution faster when the water is cold.
4. Go 10 degrees C higher
When you are creating an emulsion or working with solids that need to be heated past their melting point, a good guide for manufacturing procedures is to heat the batch 10 degrees C higher than the highest melting point of the ingredients you are using. For most emulsion this means your batch should be anywhere from 75 – 80C.
5. Twenty minutes of mixing
While it depends on your mixing tank, a minimum of twenty minutes mixing after blending the oil and water phase together is needed. If you don’t have good turnover it could take a lot longer.
6. Add fragrances and preservatives last
Since these ingredients can break down when heated, it is best to add them at the very end when all your heating and cooling is completed. This will minimize ingredient degradation.
7. Color early
Add colors early on in the batch and check the color versus a color standard. If you make a mistake you can easily pitch the batch without much cost.
8. Neutralize at the end
Finally, neutralize your formulas that require it (gels & anything with Carbomer) at the end. This should be the last ingredient you add. It will help minimize the amount of air you get in the formula.
Of course, these are just general guidelines and every specific cosmetic formulation is going to be different. Sometimes things that work easily in the lab don’t work so easily in a 2000 gallon tank so it will take some experimentation.
Do you have more suggestions? Add them in the comments below!