beta-Pinene

Description

Beta-pinene is a component of turpentine. Concentrations vary depending on the source and seem to be high er in European (Portuguese) than in Asian (Indonesian) turpentines.

Chemical Properties

β-Pinene has a characteristic turpentine odor with a dry, woody or resinous aroma.

Chemical Properties

liquid

Chemical Properties

β-Pinene occurs in many essential oils. Optically active and racemic β-pinenes are present in turpentine oils, although in smaller quantities than αα-pinene. (+)-β-Pinene, (1R,5R)-6,6-dimethyl-2-methylenebicyclo(3.1.1)heptane,; ()-β-Pinene, (1S,5S)-6,6-dimethyl-2-methylenebicyclo(3.1.1)heptane,. β-Pinene is similar to α-pinene in its reactions. Pyrolytic cleavage to myrcene, the startingmaterial for acyclic terpenes, is used on an industrial scale.Addition of formaldehyde results in the formation of nopol; nopyl acetate is used as a fragrance material. β-Pinene is produced in large quantities by distillation of turpentine oils. It is used as a fragrance material in household perfumery.However,most β-pinene is used in the production of myrcene.

Occurrence

Usually occurring together with α-pinene but in smaller amounts; the d- and l-forms are reported found in the essential oils of various Artemisae and several Cupressaceae, in coriander and cumin; the l-form is a constituent of several citrus oils. β-Pinene is reported found in over 190 natural products including apple, apricot, many citrus juices and peel oils, bilberry, cranberry, lingonberry, blackberry, currants, guava, raspberry, strawberry, basil, carrot, celery, cooked potato, bell pepper, tomato, anise seed oil, cinnamon, cassia leaf, clove, cumin, ginger, Mentha oils, nutmeg, mace, pepper, parsley, thyme, Swiss and cheddar cheese, cream, fatty fish, fried chicken, beef fat, hop oil, rum, bourbon whiskey, tea, roasted filberts, pecans, oats, soybean, plum, mushroom, sweet and wild marjoram, starfruit, mango, tamarind, cardamom, coriander, gin, rice, litchi, calamus, dill, lovage, caraway seed, buckwheat, laurel, fennel, kiwifruit, myrtle leaf and berry, rosemary, buchu oil, Bourbon vanilla, Spanish and clary sage, nectarine, crayfish, clam, cape gooseberry, anise hyssop, angelica root oil, Roman and German chamomile oil, eucalyptus oil, bullock’s heart and mastic gum leaf and fruit oil.

Uses

beta-Pinene is an important raw material for the artificial synthesis of various fragrances, camphor, borneol, vitamins A, E, and K, terpene resins, etc. GB 2760-1996 stipulates that it is a permitted fragrance, mainly used to formulate citrus flavorings such as nutmeg and lemon.

Preparation

Isolated from American turpentine; also by conversion from α-pinene; as an intermediate extremely important for the manufacture of citral, citronellol, hydroxycitronellal, geraniol, citronellal, linalool, ionones, methylionones and menthol.

Definition

ChEBI: An isomer of pinene with an exocyclic double bond. It is a component of essential oils from many plants.

Aroma threshold values

Detection: 140 ppb. Aroma characteristics at 10%: cooling, woody, piney and turpentine-like with a fresh minty, eucalyptus and camphoraceous note with a spicy peppery and nutmeg nuance.

Taste threshold values

Taste characteristics at 15 to 100 ppm: fresh, piney and woody, terpy and resinous with a slight minty, spicy and camphoraceous nuance.

Contact allergens

Beta-pinene is a component of turpentine. Concentrations vary with the source and seem higher in European (Portuguese) than in Asian (Indonesian) turpentine.

Safety Profile

Mddly toxic by ingestion. A skin irritant. Flammable liquid. When heated to decomposition it emits acrid smoke and irritating fumes.

Toxics Screening Level

It is recommended that the Initial Threshold Screening Level (ITSL) for turpentine, along with select monoterpenes (α-pinene, β-pinene, and △3-carene) be set at 1120 μg/m3 based on an 8-hour averaging time.