In recent years, consumers have developed an ever-increasing interest in natural products as alternatives for every part of their lives. Among them, essential oils (EOs) used for aromatherapy had gained great interest regarding beauty, wellness and health. Constituted of wide and numerous ranges of volatile components, EOs are known to be susceptible to degradation reactions, such as oxidation. Changes in oil compositions may result in a loss of their properties or even in a new toxicity. Most of all, oxidated oils, as stronger allergens than native oils, are sources of great concern. Therefore, the present study aims to provide new data on the stability of Eos and blend of oils when exposed to air, a crucial parameter regarding EOs stability. Finally, the peroxide value analytical method was used as a parameter to follow-up the stability and oxidation rate of samples and, in the end, highlight potential protective effect of blends from oxidation.
The results show that most of the blends in the present study were oxidation-proof, unlike the tested Eos contained which were sensitive to oxidation when they were not part of a blend (e.g., sweet orange, lemon and eucalyptus EOs).
In conclusion, the study shows an improvement of essential oil stability by blending, which has never been described in the past, and which shows a real interest of blending essential oils.