Oleoresins are semi-solid extracts composed of resin and essential or fatty oil, obtained by evaporation of the solvents used for their production.[1] The oleoresin of conifers is known as crude turpentine or gum turpentine, which consists of oil of turpentine and rosin.[2]

Properties edit

In contrast to essential oils obtained by steam distillation, oleoresins abound in heavier, less volatile and lipophilic compounds, such as resins, waxes, fats and fatty oils. Gummo-oleoresins (oleo-gum resins, gum resins) occur mostly as crude balsams and contain also water-soluble gums. Processing of oleoresins is conducted on a large scale, especially in China (400,000 tons per year in the 1990s), but the technology is too labor-intensive to be viable in countries with high labor costs, such as the US.[3]

Oleoresins are prepared from spices, such as basil, capsicum (paprika), cardamom, celery seed, cinnamon bark, clove bud, fenugreek, fir balsam, ginger, jambu, labdanum, mace, marjoram, nutmeg, parsley, pepper (black/white), pimenta (allspice), rosemary, sage, savory (summer/winter), thyme, turmeric, vanilla, and West Indian bay leaves. The solvents used are nonaqueous and may be polar (alcohols) or nonpolar (hydrocarbons, carbon dioxide).[4]

Oleoresins are similar to perfumery concretes, obtained especially from flowers, and to perfumery resinoids, which are prepared also from animal secretions.

Use edit

 
Oleoresin Capsicum tear gas being sprayed on a guardsman

Most oleoresins are used as flavors and perfumes, some are used medicinally (e. g., oleoresin of Cannabis). Oleoresin capsicum is commonly used as a basis for pepper sprays. There are also uses known in the manufacture of soaps of cosmetics, as well as coloring agents for foods.

References edit

  1. ^ Commission, British Pharmacopoeia (2009), "EXTRACTS", British Pharmacopoeia, vol. 3, ISBN 978-0-11-322799-0
  2. ^ "Turpentine". Britannica. Retrieved 2022-03-02.
  3. ^ Lars-Hugo Norlin (2002). "Tall Oil". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a26_057. ISBN 978-3527306732.
  4. ^ George A. Burdock (2010), Fenaroli's Handbook of Flavor Ingredients (6th ed.), Taylor & Francis, ISBN 978-1-4200-9077-2