When working with tropical butters in formulations, you’ve likely been disappointed by the appearance of bloom at some point.
This rough and grainy texture can appear at the top of your product, ruining it both during production and later stages. What goes wrong and how can you banish bloom for good?
Whether your final formulation is for a body butter or lipstick, tropical butters are versatile ingredients that add many desirable properties to end products. They are great to add in formulations because of their richness in solid fats, be it shea, cocoa, or illipe butter. Their high-fat content is, unfortunately, also what can make them more difficult to work with when they are in their raw state. When fat goes from liquid to solid, the fat molecules form nuclei that crystallize into patterns, and it’s at this crystallization stage, where things can go wrong.
It all comes down to crystallization
As fat becomes solid, it can form different types of crystals. When it takes longer to reach a crystallized state, there is a greater risk of bloom. This is because slower crystallization leads to larger fat nuclei that crystallize into grains – just what you don’t want! Every time your formulation goes from liquid to solid, crystallization happens. So, any time there are temperature changes, there’s a risk. This can be when the product cools off in production, while in storage, or during transportation.
For example, if the product is being transported in a hot truck at 40-degree temperatures, the fats in your product will melt. At a later stage they will solidify, and who knows into what crystals? Even on a shop shelf or in a consumer's handbag, the product can be exposed to temperature changes throughout the year. Tropical butters in their raw state are sensitive. So, what can you do to make them more stable and reliable?
Processing for a softer, smoother result
The secret lies in a process called interesterification. This is a chemical term for rearranging the fatty acid chains of the natural tropical butter. The fatty acid composition is kept the same, but the chains are cleaved, shuffled, and reattached. This processing leads to a product that is much more resilient than the original raw product, as it now crystallizes into a stable form quickly, reducing the risk of bloom. But that’s not everything. The processed tropical fat also gains excellent sensory properties.
At AAK, we have made use of this processing method to develop our AAK Soft Technology, where we turn raw tropical butters into products that offer softer textures. The rapid crystallization of these also leads to a smoother and glossier formulation. For example, Lipex SheaSoft TR offers a creamy and luxurious skin feel and works great as a texturizer, moisturizer, or sensory enhancer in anything from lip balms to skin creams. As the processing results in higher melting points, the product also offers excellent thermal stability and a longer shelf life. But best of all, above the enhanced aesthetics and premium sensations, there’s no trace of that troublesome issue known as bloom.
Do you want to learn more about crystallization and interesterification?
