The Importance of Stability Testing Cosmetics and Personal Care Products


 November 13, 2019

Throughout their lifecycle, cosmetics will be exposed to a number of different elements during manufacturing, storage, transport, retail and consumer use. Stability testing cosmetics can help to accelerate and predict the effects of stresses, such as temperature, product exposure conditions, microbiological stability and much more.

Currently the FDA Code of Federal Regulations does not provide any uniform stability testing protocols for cosmetics outside of specific OTC product categories, such as sunscreen, antiperspirant, medical based products (ie: dandruff shampoo). As such, it’s important that each manufacturer has their own stability testing protocol that efficiently addresses the product’s unique formulation concerns. 

Read More: Understanding Regulatory Requirements for Cosmetics: USA vs Global

3 Forms of Stability Testing for Cosmetics

In this three-part series we will review three common forms of stability testing used for cosmetic products: physical and chemical integrity tests (part 1), microbiological stability tests (part 2) as well as packaging stability tests (part 3).

What is Stability Testing of Cosmetics?

Stability testing cosmetics and personal care products is an important process to ensure that a new or revised formula meets the chemical, physical and microbiological quality standards. This experiment is important to measure and document the stability of cosmetics, before they can be sold to consumers, and identify any stability issues related to recalls. As cosmetic manufacturers can attest, beauty product recalls are not only costly and labor intensive, but they can also seriously damage brand reputation.

Stability testing of cosmetics can provide valuable insight on the product’s formulation, by measuring factors such as:

  • Ability to resist microbial intrusion 
  • Degradation rate of ingredients
  • Chemical stability of product under various elements
  • Reactivity to packaging and transport
  • Impurity exposure during the manufacturing process 
  • Formulation response to elements such as heat, light, humidity 


Physical and Chemical Integrity Tests

Physical and chemical integrity tests evaluate viscosity, color, light exposure, fragrance, pH, texture, flow, and emulsion stability. Common physical and chemical integrity tests for cosmetics include:


  • High Temperature Testing- Beauty products naturally degrade over time; this is known as a product’s shelf life. High temperature testing is commonly used to predict shelf life for cosmetics and personal care products. 
  • Freeze/Thaw Studies- Cycle testing is an even more rigorous test that places the product under tremendous temperature stress. Also known as freeze/thaw studies, if the product passes this kind of test, it is a good indicator of long-term product stability.
  • Centrifuge Testing- Centrifuge testing is an important test for liquid and cream based cosmetics. This test is helpful to predict creaming, one of the initial signs of separation and impending emulsion instability. 
  • Light Exposure Testing- The objective of light exposure testing is not only to help predict how the formula’s effectiveness will react to UV exposure, but also to determine any potential discoloration of the product. 


By measuring how well cosmetics will resist these common stresses, manufacturers can better determine any vulnerabilities that may need to be addressed and monitor potential shipping, storage and display conditions. 

Stability Testing Consultative Support

Do you have questions about stability testing cosmetics and personal care products? At Kinetik, we are not just a leading curator of high-quality, raw cosmetic ingredients, we provide in depth consultative support and resources to guide beauty brands through the appropriate testing measures.

Learn more about our approach.

Contact us at (732) 335-5775 for more information. We are headquartered in the USA, but we work with clients and represent suppliers worldwide.