Skincare products have a limited shelf life because fatty acids in the products can form volatile oxidation products, which create an unpleasant odour. Therefore, when manufacturers want to develop a product, it is important to understand the oxidation process the product will undergo, in order to determine its shelf life.
Until now, manufacturers have had to set aside at least six months to study the oxidation process that takes place, which creates a bottleneck in product development. A PhD project from the National Food Institute has now made it possible to expedite the oxidation process, which enables manufacturers to examine products’ shelf life in just one month.
Birgitte R. Thomsen has developed a method in which different substances are added to the product to speed up the chemical reaction that otherwise occurs naturally over time. Her tests have produced the same results, regardless of whether the oxidation process is tested using the new or the traditional method.
New substances identified
In her studies, Birgitte R. Thomsen has also identified two substances not previously reported in skincare products that develop during storage and contribute to unwanted changes in the creams’ smell. If manufacturers are to prevent these substances from forming in their skincare products, it is important to know how they are formed.
Birgitte R. Thomsen has identified how the substances are most likely formed. The study has provided thorough evidence that one of the substances is a degradation product from a sunscreen in the cream. The other substance may be a degradation product from a chemical substance in the cream, or it may have migrated from the packaging. Further research is needed to determine the exact reaction route.