Terpeneless

Terpene-based resins Terpene hydrocarbons Terpeneless lime oil Terp ene-phenolics Terpenes... 

Component CAS Registry Number Stmcture number Distilled oil, % Terpeneless oil, %... 

Because of its more interesting odor and flavor properties, many perfumers and flavorists prefer to use a terpeneless lime oil. A typical analysis is shown iu Table 10 (26). 

The determination of hydrocarbons is not often required, but is a matter of some importance in the case of the so-called terpeneless and sesquiterpeneless oils, especially those of lemon, many commercial samples of which contain appreciable quantities of hydrocarbons. 

TERPENELESS OIL. An essential oil from which the teqoene components have been removed by extraction and fractionation, either alone or in combination. The optical activity of the oil is thus reduced. The terpene-less grades are much more highly concentrated than the original oil (15—30 times). Removal of terpenes is necessary to inhibit spoilage, particularly of oils derived from citrus sources. O11 atmospheric oxidation the specific terpenes form compounds that impair the value of the oil for example, d-limonene oxidazes to carvone and y-terpinene to p-cymene. Terpeneless grades of citrus oils are commercially available. 

The term folded oils refers to concentrated oils. This typically involves a distillation process however, alcohol washing can also be used. Alcohol washing is based on the insolubility of d-limonene in 60% to 70% ethanol. These processes predominately remove terpene compounds, although aldehydes (octanal) are also reduced. Oils that are more than 20-fold concentrated are called terpeneless oils and are more stable. Distillation is predominately used by flavor houses. Flavor houses purchase cold-pressed oil, which is concentrated and fractionated. These fractionated portions are sold for flavorings or flavor precursors. 

Many other processes can be applied to concretes, absolutes, resinoids, and essential oils to obtain products with special characteristics. For example, decolorized products may be obtained by extraction with appropriate solvents to eliminate highly colored components. Colorless products may be obtained by fractional molecular distillation under vacuum. Yet another type of product is obtained by vacuum codistillation using a suitable solvent. Many essential oils, particularly citrus oils, contain high levels of insoluble terpene hydrocarbons, which can be removed by fractional distillation or by countercurrent extraction to produce concentrated or terpeneless oils. 

Emulsions, destabilization, 173. See also Creams, Lotions Encapsulation, 175 Enfleurage, 20, 134 Enzymes, 169 Escape, 104,129, 269 Essential oils, 19 terpeneless, 21 Esters, 207... 

Redistillation of an essential oil can remove terpenes (deterpenation) to make the oil more alcohol-soluble and longer-lasting. This is most commonly done in citrus oils and they are called terpeneless or folded oils. 

Terpeneless essential oil An essential oil with all or part of the terpene content removed by solvent extraction or vacuum fractionation. 

A continuous cyclic operation between the adsorption at a lower pressure and the desorption at a higher pressure, involving the rinse step to remove the solutes in the void region of the adsorber, was demonstrated for citrus oil processing with silica gel adsorbent in SC-C02. Terpeneless citrus oil was succesfully obtained in the desorption step and blowdown step. The proposed system showed the feasibility of the continuous operation of the cyclic adsorption process. 

Citrus oil dominates this class of essential oil. It is obtained by the cold press method with the exception of lime oil, which is also prepared by steam distillation of essential oil separated during the production of juice.106,107 Aside from bergamot, these oils are primarily monoterpene hydrocarbon mixtures of which (if)-limonene (3) is usually the dominant compound. Since odor contribution of this monoterpene compound is low, it is often removed by distillation or repeated solvent extraction. The resulting oil rich in odor-active compounds is called terpeneless oil and is used extensively. In the case of bergamot and lemon oils, psoralen derivates like bergaptene (64) causing photosensitivity are problematic, and those for fragrance use are rectified to remove it (Table 8). 

Essential oils boil at elevated temperatures, but many cannot be directly distilled without decomposition. Vacuum, steam, and fractional or molecular distillation are often used for their manufacture. Fractional distillation removes traces of water, resinous materials, colors, terpenes, and sesquiterpenes from the distillate. This process improves solubility and enhances flavor intensity. Sesquiterpeneless oils are more soluble than terpeneless oils because of the removal of head and tail fractions (e.g., waxy residues). Most common sesquiterpeneless oils used in the pharmaceutical industry include oil of orange and oil of lemon. 

Natural ingredients have been used since antiquity to flavor foods and to make early medicines palatable. Honey was and remains a sweetener and flavoring agent. Wine was used as a crude infusorial in medicinal herbs. Modern use of natural flavors in pharmaceuticals is limited, because they are often unstable and their quality is unpredictable from season to season. The most commonly used natural flavors are terpeneless citrus oils, which are stable if well protected from... 

See terpeneless oil. Further information can be obtained from the Essential Oil Association of U.S. 

Citrus fruits contain peel oil, the essence from which oil is obtained during concentration of the juice process. Citrus oils are characterized by a high percentage of terpene hydrocarbons (limonene, C10H16), which contribute little to aroma. The unique characteristics of limonene are its relative insolubility in dilute alcohol and its susceptibility to oxidation, causing off-flavor production. If the monoterpenes are removed, the resulting oil is called terpene-free or terpeneless oil. Aldehydes, esters, and alcohols are the main contributors to the aromas of citrus oil. These compounds are relatively polar and soluble in water therefore, they are satisfactory for applications in food and beverage. 

Perfume materials obtained in this way are referred to as essential oils. Thus, for example, the oil obtained by steam distillation of lavender is known as the essential oil of lavender, or lavender oil. Sometimes, the monoterpene hydrocarbons are removed from the oils by distillation or solvent extraction to give a finer odour in the product. The process is known as deterpenation and the product is referred to as a terpeneless oil. This is, of course, a misnomer since, for example, the major component of lavender oil terpeneless is linalyl acetate, a monoterpene. 

Orange oil, terpeneless (Citrus sinensis (L.) Osbeck) 2812 Ortho 199 1507... 

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