Formulation and Quality Evaluation of Protective Lipstick with Oenothera biennis L. Oil

The aim of this work was to design a lipstick with evening primrose oil (EPO) for daily protection of the lips. The formulated lipsticks contained only natural compounds: evening primrose oil, yellow beeswax, cacao butter, vitamin E (preservative), Tangerine essential oil (fragrance), β-carotene (coloring agent). Design-Expert® 6.0 statistical modeling program was used to design mixtures of ingredients for optimal lipstick composition. The physical properties - pH value, melting point and hardness (texture analyzer) were evaluated. Water extracts of EPO and produced lipsticks were tested for antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant assay. Sensory analysis was performed with trained volunteers using questionnaire survey. The results of physical properties confirmed that all samples after production meet the quality requirements. Sensory analysis showed that lipsticks’ qualities, such as spreadability, hardness, residual layer, etc., were highly dependent on the balance between oils and waxes. Therefore approximately 45-55% of base should consist of hard waxes in order to maintain suitable texture. Although sensory analysis and antioxidant assay has shown that composition of lipstick, containing the biggest amount of evening primrose oil (75.21%) had the best features as well as the greatest antioxidant activity (24,84 ± 1,37%). Based on the analysis of the results of textural, organoleptic and other quality characteristics, the following composition of organic lipstick was chosen: Evening primrose oil 54,0 %, Beeswax 25,0 %, Cacao butter 25,0 %, Vitamin E 1,0 %, β-carotene, Tangerine essential oil. According to the obtained stability test results, the designed lipstick’s quality remained appropriate at least six month after production at room temperature 252°C temperature