Topics - Essential Oils
The essential oil
of a material is the name given to the mixtures of substances extracted from a biological system and will contain the essential components that provide the characteristic odor or flavor of that material. Examples would be peppermint oils, clove oil, musk etc. Essential oils are usually a highly complex mixture of a wide variety of substances (usually relatively volatile substances at least with a significant vapor pressure). The oil may often be simulated by a fairly simple mixture of synthetic compounds blended in the same proportion as the original oil but the odor or taste often lacks the authenticity of the original essential oil
. Essential oils are extracted from the biological matrix by a number of different methods. The material is sometimes leached with water and the oil steam distilled from the aqueous mixture. The natural material may also be solvent extracted and the oil recovered by distillation. The use of heat, however, must be used with considerable care as many of the components of essential oils are thermally labile
. Essential oils can often be extracted by a form of gas-liquid distribution. Large containers are filled with trays containing animal fat and flowers loaded onto the trays. By diffusion the essential oils in the flowers become distributed into the fat and after a few days the flowers are removed and the essential oils distilled from the fat.