Coriander seed CO2 extract

Floral, orange, sweet spice, light wood, with a fatty-aldehydic touch. Fresh and soft; the CO2 extract is rounder than the oil with a light roasted-seed note.

Coriander seed CO2 extract has no dedicated standard in the IFRA 51 index. Linalool is its main constituent; linalool is under an IFRA peroxide specification and an EU-labelled allergen above threshold.

Oxidised linalool forms hydroperoxides that sensitise skin. Store dark, sealed and cool; an antioxidant may be added.

Coriandrum sativum is an annual umbellifer. In Vietnam the leaf (ngò, rau mùi) is more familiar than the seed, but in flavour and fragrance the dried seed is the main source. Seed is grown on a large scale in Russia, Ukraine, Bulgaria, Morocco and India.

Leaf and seed smell very different. The leaf is rich in long-chain aldehydes such as decenal, giving a green, soapy note. The seed is rich in linalool, giving floral and orange notes. The library has separate oil pages for leaf and seed.

CO2 extraction uses compressed carbon dioxide as the solvent. Under subcritical conditions CO2 takes mainly the volatile fraction, giving a product called a select extract. Under supercritical conditions it also takes lipids and non-volatiles, giving a total extract. On depressurisation the CO2 evaporates completely and leaves no solvent residue.

The total extract also holds seed fatty oil, rich in petroselinic acid. The select extract is mainly volatile and close to the oil, but keeps some extra esters and a light roasted note.

In perfumery coriander seed CO2 serves floral-spicy tops in colognes, florals and woody fragrances. It bridges citrus and flowers and pairs with lavender, rose, cardamom and woods.

Since linalool dominates, quality depends on preventing oxidation. Aged material or bottles opened many times should have their peroxide value rechecked.