Aging of Essential Oils

Peroxidation and Intramolecular Reaction Olive oils become rancid over time. Rancidity is a chemical modification of the molecular structures of vegetable oils. The same chemical mechanisms also operate on essential oils. The presence of oxygen naturally dissolved in the oils initiates these chemical reactions. They accelerate in the presence of light, air, temperature fluctuations, or various impurities. The reaction mechanism of this "aging" is divided into two stages: peroxidation and intramolecular reactions (or propagation phase). Scientific literature describes several examples of peroxidation. Here is the one for linalool, which is abundantly present in essential oils. (Examples: lavender, lavandin, linalool thyme, rosewood, clary sage, etc.). In this scheme, linalool first undergoes peroxidation. It produces a new compound: 7-dydroperoxy-3,7-dimethyl-octa-1,5-diene-3-ol.