contract manufacturer scaling up cosmetic production

Scaling Up Your Production: Not Just Multiplication

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Scaling up products from a home batch to larger-scale production often presents many surprising challenges. It is not simply a matter of multiplication to get the same end product—the very nature of large scale production changes heating and cooling times, temperatures, ratios, and more. Instead of receiving an unpleasant shock between prototype and production phases, let’s explore what is likely to be an issue and how to manage it. Here’s a rough overview with some thoughts to keep in mind, and we’ll elaborate more in the future.

 

Something Almost Always Must Change

Formula scale-up is not as simple as multiplying. I liken cosmetic manufacturing to baking, though I have spoken to some folks who have gone from baking and/or food science into cosmetic formulations and they say cosmetics are far less predictable. The analogy I use is that in a home kitchen when one is baking a cake. They can double or triple a recipe and still use the same ingredients, measuring tools, and baking time. But when a yield increases from that cake needing to feed 8 people to now 800 people, things change.

  • The usual process of scaling up starts with a prototype in the lab, often just a pound or so, then moving up to a “pilot batch” of perhaps 100 pounds. This might then culminate in a final production batch of 1,000 pounds. Along the way, each step offers something useful.
  • Ingredients may not behave in the same way, so they may need to be adjusted or changed to achieve the desired result. For us in cosmetics, it’s electrolytes, polysaccharides and numerous others that can’t simply be evenly multiplied when scaling up.
  • One of the biggest factors in selecting ingredients for a formula is knowing how they will scale. We try to ensure is to not use an ingredient whose stability may not meet the needs of a larger batch and process. This situation is one of trial and error as well. Two different preservatives come to mind where we have had to waste thousands of pounds because their use was not scalable in the same manner we had used in the smaller batch.  Trial and error form the base of scale-up.

General Issues to Consider

Reviewing the above considerations, you can see how the finished product may have a different texture or viscosity as a result of scale-up. So products often need to be “reworked” until the production batch matches the approved prototype. 

Here are some other examples of quite common issues that arise.

  • 1) The length of “cooking” time will change and there is almost no way to determine how to translate the cooldown of 1 pound in the lab, to a 200 pound pilot batch, to a 2,000 pound production batch.
  • 2) Another part of production that is impacted by scale-up is the ingredient delivery method one chooses to use. For example, in a laboratory setting, incorporating a chunk of Shea Butter into the recipe is easy—just cut it into pieces and transfer it into the mixer. However, when one is handling a 50-pound block of Shea butter, the method is vastly different.
  • 3) Will the setup of your production area affect the product? This might include sizes and types of pipes and pumps that product will pass through.
  • 4) Can ingredients still be manually added, or are their characteristics such that they need to be slowly sprinkled over the surface of a now much wider-diameter tank? Maybe they need to be mixed at a very slow rate, or all of a sudden you have to turn up the RPMs greatly.
  • 5) Do you need to prepare ingredients in some way before they put them into the mixer or another part of the process? Is this understood each time before scale up?

Mixing Considerations

Mixing is a complicated science. Many types and sizes of mixers are available to meet specific needs of viscosity, volume, and material. Determining which type such as high shear, static, milling, baffled or not, etc., and also the size of the mixer to buy, is complicated. A wrong decision can be costly from a quality, production, and replacement cost standpoint. Questions that not only need to be answered BEFORE scaling up but also might have been answered incorrectly and then need to be looked at again are:

1) What is the desired viscosity of the product throughout the mixing cycle? 

2) What is the desired pH between each phase? 

3) What are the color, odor, and rheology (the flow of a liquid) between at the highest temp and then at the lowest? 

4) What type of mixing does one need to accomplish? For instance, incorporating Jojoba wax beads into a cream base requires folding, whereas ensuring powdered ingredients are mixed incorrectly we would shear-mix to break up clumps.

5) Will one need to reevaluate the order of additions? A thick mixture, when scaled up, can require much more powerful equipment to mix it at its thickest point, but perhaps changing the order of addition will prevent the product from becoming as thick. 

6) Can one piece of equipment be used to scale-up multiple products? One will need to evaluate the products’ ingredients, viscosities, and solids content to determine this.

7) How much will the diameter of the tank and mixing blade affect the mix and temperature? Smaller blades in larger tanks have a harder time of thoroughly mixing all the product, much of which can get stuck to the side of the tank and never properly integrate without a person routinely scraping the sides. So not only is mixing a greater challenge in larger tanks, but the temperature can be noticeably different on the sides of the tank compared with the center.

Temperature and Scale Up

Now if everything I mentioned isn’t bad enough, there’s another big problem here: the larger surface area and greater volume of production versus lab or pilot batches. The area and volume will greatly impact heat transfer for both heating and cooling. When heating larger quantities, it is tempting to increase the temperature to increase the heat transfer to the product.  But for some heat-sensitive ingredients, which many in the cosmetic world are, the higher temperatures can cause products to burn or simply to oxidize too fast and have an odd color change; 2 problems that affect the quality of the product and the cleanup. So with this we need to ask: 

1) How will the times and temperatures of heating and cooling be impacted?

2) How will the heat treatment impact the scent and color of the product?

3) Will the heat treatment affect the preservative negatively and if so, will we have to wait 5 days for our bacterial assay to simply fail and we have to start all over again? 

4) Will heating and/or slow cooling affect the raw material selection and order of additions?

Pilot testing can help determine the most efficient process for these costly process and utility changes in methodology. The real way to avoid major problems before a production run is taking the time to run pilot batches and tweak formulas and methodologies until it’s as close as possible to being ‘nailed down’. As you can see, more time and energy than you might desire is involved in scale-up. Your account executive understands this and is here to help!

We’d love to hear what your own issues with scale-up have been and how you tackle them.

 

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2 years ago

Very informative! Thank you for the article, this put scaling up and possible problems into perspective. I’d love to hear a little more about the 2 failed preservatives that were encountered during scale ups. Not necessarily the type, but what went wrong and why? I think this would be a great example for how and why some ingredients may not work when scaling up.

I’ve experienced issues when scaling up production of cold process soap. It seems when working with bigger batches the soap goes to trace much faster than when handling smaller batches. Once I had a batch that went to trace and thickened so fast I barely had enough time to pour the batter before it set up. After reading this article I understand this is likely due to the different temperatures of being in a vessel with less surface area to cool, causing the soap to heat up faster. I’ll now know next time to use an appropriately sized vessel that provides that same surface area as smaller batches for mixing the oils and lye.

Admin
2 years ago
Reply to  Julie

Hi Julie, thanks for your comment and interesting about the soap and thickening! Here is what Laura has to say about the preservative example she mentioned in the article:
“Some time ago, we had had the products challenge-tested by a third party and were given a 3 year shelf life (which is pretty good!).

We scaled the products up to 2000 lb, and five months afterwards the customer called to report mold. Not only was it mold but it was about 3 inches thick of it in each drum! Our bacterial testing in house when we made it was good, so of course we sent it on to the customer. When they opened their drums 5 months later with that mold, we pulled our batch retention samples and lo and behold they had it too. We called the manufacturer of the preservative and after 1.5 hours on the phone, we found out that there were contraindications to the preservative in scale up. It was a hard and expensive learning for us, but we’re happy we now know this and can manage it better in the future. Some ingredients just don’t do well in scale up.”

Wes
2 years ago

Can you list what the preservatives used were? The actual names? We’re they plant based?

Admin
2 years ago
Reply to  Wes

Hi Wes, thanks for your question. Basically it completely depends on other ingredients, methodology, and more, so we are not comfortable calling out any specific ingredient(s) when one might work great in one formula but fail in another. We are happy to consult with you if you choose to move forward with us, however, and of course apply our knowledge to any formula discussions we may have down the line.

Dave Davenport
1 year ago

As a company who is in the process of Leaving the house and going bigger into a commercial space I so appreciate this article. We started noticing these effects simply going from 1 gallon batches to 10 gallon batches so I can only imagine the 2000 gallon batch.
With that being said we love your products and are so thankful for all the help that comes with them

1 year ago

Thank you so much for that article .
I create an oil blend which has been patent for its unique benefits and for the system I process the ingredients. Speed and heat are crucials steps to maintain the integrity and the effectiveness of the ingredients
Your articles are so well written , thank for sharing and clarifying misleading informations from fake blogs and social media
Romina

Admin
1 year ago
Reply to  Romina

Glad you enjoy them, Romina!
Just let us know if you ever have any questions!

Cheers,
Brandon