Terpene

Terpenes are a large family of naturally occurring aromatic compounds produced by many plants, including hemp and cannabis. They are primarily responsible for the characteristic scents and aromas of the plant world and contribute to the olfactory identity of each hemp variety. In the plant, they are synthesised in the trichomes, where they are produced alongside cannabinoids.

Terpenes are not unique to cannabis. They are found in many plant species, including citrus fruits, pine trees, lavender, rosemary, hops, pepper and certain aromatic flowers. Their presence contributes to the chemical richness of plants and the great diversity of aromatic profiles found in nature.

The source of hemp aromas

Terpenes play an essential role in the aromatic profile of hemp flowers, resins and extracts. They are responsible for the different scents found in different varieties: citrus, fruity, floral, woody, earthy, resinous, spicy and even menthol notes.

Each variety has a unique combination of terpenes. It is this composition, rather than a single isolated terpene, that determines the overall aromatic signature of a flower or product.

A highly diverse family of molecules

Several thousand terpenes have been identified in the plant kingdom, including several hundred found in cannabis. The best-known include myrcene, limonene, pinene, linalool, caryophyllene, humulene and terpinolene.

Each terpene has a particular chemical structure and contributes differently to the plant’s aromatic profile. The relative proportions of these molecules vary considerably from one variety to another.

Produced in the trichomes

In hemp, terpenes are primarily synthesised in the trichomes, the small resin glands covering the flowers. These structures also produce cannabinoids, which explains why these two families of compounds are often studied together.

The quantity and diversity of terpenes depend on many factors, including genetics, growing conditions, climate, harvest stage, drying, curing, and extraction and processing methods.

Sensitive compounds

Terpenes are relatively volatile molecules. Excessive exposure to heat, air or light can alter their concentration and a product’s aromatic profile.

This is why harvesting, drying, storage and processing conditions play an important role in preserving the aromatic characteristics of hemp.

Essential to the study of hemp

Terpenes now occupy a central place in the analysis of hemp varieties. They are studied alongside cannabinoids to better characterise the chemical profiles of flowers, extracts and other cannabis-derived products.

Understanding terpenes makes it possible to better interpret aromatic profiles, certificates of analysis (COAs) and the differences observed between the many hemp varieties available today.