Chemistry of Oils - Vocabulary Flashcards (Notes)

Vocabulary flashcards covering key terms, concepts, and definitions from the Chemistry of Oils worksheet notes to support exam preparation.

Distillation

A method of extracting essential oils using steam to vaporize volatile oils, then condense and collect the oil.

Enfleurage

An old extraction method that uses cold vegetable fat to absorb volatile essential oils.

CO2 extraction

A modern solvent-free method using supercritical CO2 to dissolve and extract essential oils.

Helium

A noble gas with no relevance to essential oil chemistry.

Terpene

A hydrocarbon class that forms the building blocks of many essential oils; often unsaturated and lacking other functional groups.

Azulene

A blue hydrocarbon found in some essential oils, notably German chamomile.

Solubility of essential oils

Essential oils are generally soluble in fats and alcohols, but not in water.

R–OH group

Hydroxyl functional group; characteristic of alcohols.

Maceration

Extraction method where plant material soaks in a solvent at room temperature to release oils.

Wheat germ oil

Carrier oil that can act as a preservative due to its antioxidants.

Hydrocarbon

An organic compound made up only of hydrogen and carbon.

Monoterpene

A terpene built from two isoprene units (C10H16); common in many essential oils.

Phenol

A compound with a hydroxyl group attached to an aromatic benzene ring; phenols often end with -ol and can be more irritant/toxic than simple alcohols.

Sesquiterpene

A terpene built from three isoprene units (C15H24).

Linalyl acetate

An ester commonly found in clary sage essential oil.

α-Pinene

A monoterpene hydrocarbon commonly found in Cypress and other conifer oils.

Geraniol / Citronellol

Monoterpene alcohols; key components of Geranium oil.

Terpinene-4-ol

A monoterpene alcohol; a major constituent in Tea Tree oil.

Clary sage (Salvia sclarea)

Popular name for Salvia sclarea; used in aromatherapy and perfumery.

Blue gum

Popular name for Eucalyptus globulus/radiata.

Geranium (Pelargonium graveolens)

Popular name for Pelargonium graveolens; used for its rose-like scent.

Expression (cold-press)

Mechanical method to extract oils, especially from citrus peels.

Analgesic

Property of a substance that relieves pain.

Expectorant

Property that helps expel mucus from the respiratory tract.

Emetic

Substance that induces vomiting.

Phenolic properties

Phenolic constituents can be hepatotoxic and irritant; use in low dilution and short-term applications.

Dermal absorption – Stratum Corneum pathway

Polar route where absorption occurs across cells and intercellular spaces in the outer skin layer.

Dermal absorption – Lipid pathway

Lipid route through the intercellular lipid matrix of the skin.

Olfactory mucosa to olfactory bulb

Inhaled essential oils are absorbed by the nasal mucosa and transported to the olfactory bulb.

Anosmia

Loss or inability to smell; may persist after infection in some cases.

Limbic system and essential oils

The limbic system governs emotion; essential oils can influence mood and emotional responses via this system.