Terpineol is usually a mixture of its four isomers, alpha-, beta-, gamma- terpineol and terpinen-4-ol. Alpha-terpineol is the major constituent. Sources of terpineol are found from a variety of sources such as cajuput oil, pine oil and petitgrain oil. Terpineol is a commonly used in the flavor and fragrance industry as an ingredient in cosmetics and perfumes because of its pleasant odor which resembles lilac.
Terpineol can be extracted from essential oils such as pine oil, petitgrain oil and cajuput oil. The essential oils are recovered through the physical separation process of partial pressure steam distillation, where steam is passed through plant material to separate the essential oil. Further distillation of the essential oil extracts terpineol from other components in the oil.
A more common manufacturing process for terpineol is from synthesis of the more abundant chemical species alpha-pinene. Alpha-pinene contains a four-membered ring, making it a reactive hydrocarbon, prone to skeletal rearrangements. Alpha-pinene undergoes hydration with aqueous mineral acids, using weak acids or acid-activated silica gel as catalysts. The process produces crystalline cis-terpin hydrate, which then undergoes partially dehydration to produce alpha-terpineol.
Due to its pleasant odor similar to lilac, terpineol is commonly used in the manufacturing of soaps, perfumes, cosmetics, antiseptic agents and is considered one of the most frequently used fragrance compounds.
Alpha-terpineol possess a wide range of biological properties that attract a great interest in the medicinal field. Studies have found that alpha-terpineol possess antiulcer, antioxidant, as well as skin penetration enhancing activity.
Terpineol is used in cleaning agents because of its disinfecting properties, as well as an odorant. In the mineral benefit industry it is also used as a metal flotation agent.