M. Stockstrom, A. Thiemann
Formulators are facing new challenges when protecting oil-containing systems such as cosmetic O/W (oil suspended in water) emulsions against oxidative deterioration. These challenges are a result of both growing consumer awareness of sustainability and the increased use of natural raw materials. As a result, planning cosmetic formulation concepts is becoming increasingly complex. The remedy of choice against lipid oxidation is the use of antioxidant systems, such as tocopherols. An initial prerequisite for their targeted and careful use in cosmetic formulations is reliable analysis of their antioxidant efficacy. Unlike the requirements for the formulator, current measurement methods do not reflect the conditions of a product’s life-cycle associated with cosmetics. A method developed by Evonik for testing oxidative stability can overcome this. This method is based on measuring oxygen levels above the formulation, within a closed system and under conditions relevant to cosmetics. In this study, we investigated the product-protective efficacy of certain antioxidant products (dermofeel® Toco 70 non-GMO, dermofeel® TocoBalance, dermofeel® AP MB) in O/W emulsions with different emulsifier systems (dermofeel® GSC SG and Distearyldimonium Chloride and symbio®muls GC MB). The results exemplify our ability to assist formulators in their planning and raw material selection by providing precise information on system-dependent efficacies, consisting of interactions, synergies, but also pro-oxidative effects.