Methods Used to Produce Essential Oils
Distilling: Extracting essential oils by distillation producing the volatile & water insoluble parts of a plant.
Steam Distilling: Extracting essential oils by steam distillations. Used for most essential oils.
Pressing: Extracting oil from the plant by applying pressure. Citrus Oils are usually extracted this way.
Cold Pressing: A certain amount of heat is used to help release the oil, usually not higher than 60-80 C (140-176 F). Above this temperature, the process cannot be classified as cold expression.
Solvent Extraction: Extracting delicate oils that can be damaged by distillation or other methods using solvents to dissolve the oils.
Absolute Solvent Extraction: Absolutes are extracted from concretes using alcohol which is later removed.
Resinoid Solvent Extraction: Resinoids are resins dissolved in a solvent such as benzene or alcohol. Resins are natural solid or semi-solid substance produces by plants or trees. Vanilla Oleoresin is an example.
Fractionation: Additional processing of essential oils to remove "undesirables".
Fractionation, Folding: Oil is re-distilled removing some but not all of the terpenes in the oil.
Fractionation, Terpeneless: Oil is re-distilled and all terpeneless are removed.
Fractionation, Rectification: Part(s) of the oils is removed using re-distillation, heating or chilling.
Reconstituting: Blending a combination of natural chemicals to mimic the composition of an essential oil as found in nature, e.g. Melissa & Yuzu.
Natural Reconstituting: All components in blend are natural (from other plants).