Oleoresins Solvent Extraction

Spice essoitial oils frequently lack the full, rounded profiles associated with the use of ground herbs and spices. In certain instances they are totally devoid of characteristic flavoring attributes contributed by nonvolatile components in the natural material These can be recovered by extraction of selected, dried and ground herbs and spices. In practice, organic solvents are chosen that optimally dissolve both the essential 

Spice Volatile Oil Content (% v/v) Spice Volatile Oil Content (% v/v) 

China star About 30 Fenugreek Trace 

Source From Heath, H.B., G.A. Reinecdus, Flavor Chemistry arid Technology, Van Nostrand Reinhold, New York, 1986. With permission. 

Two main categories of solvents are widely used and these are listed in Table 8.10. 

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Oleoresin. Natural oleoresins are exudates from plants, whereas prepared oleoresins are solvent extracts of botanicals, which contain oil (both volatile and, sometimes, fixed), and the resinous matter of the plant. Natural oleoresins are usually clear, viscous, and light-colored Hquids, whereas prepared oleoresins are heterogeneous masses of dark color. 

The oleoresin is obtained from turmeric powder by solvent extraction. Solvents approved for use by European Commission are ethylacetate, acetone, carbon dioxide, dichloromethane, n-butanol, methanol, ethanol, and hexane. The U.S. Food and Drug Administration (FDA) also authorized the use of mixtures of solvents that include those mentioned earlier plus isopropanol and trichloroethylene. After filtration the solvents must be completely removed from the oleoresin. 

Paprika contains capsombin and capsanthin (Fig. 8.3) which occur mainly as the lauric acid esters, and about 20 other carotenoid pigments. Paprika is produced in many countries which have developed their own specialties. Cayenne or cayenne pepper, produced from a different cultivar of C. annum, is usually more pungent. C. frutescens is the source of the very pungent Tabasco sauce. Paprika oleoresin is produced by solvent extraction of the ground powder. Obviously paprika supplies both flavor and color and its use is limited to those products compatible with the flavor. The recent rise in demand for tomato products in the form of pizza, salsa, etc., has increased the demand for paprika. Paprika is used in meat products, soups, sauces, salad dressings, processed cheese, snacks, confectionery and baked goods.1018... 

A ginger oil is produced from the steam distillation of dried root, and used in beverages, candies, and perfumes. Ginger oleoresin, or solvent extract, is now used as a flavoring agent as well. 

The resinoids described above should be distinguished from prepared oleoresins (e.g., pepper, ginger, and vanilla oleoresins), which are concentrates prepared from spices by solvent extraction. The solvent that is used depends on the spice currently, these products are often obtained by extraction with supercritical carbon dioxide [223a]. Pepper and ginger oleoresins contain not only volatile aroma compounds, but also substances responsible for pungency. 

Pepper oleoresin is produced by solvent extraction and, unlike the oil, contains the principal pungent compound, piperine [94-62-2], along with some essential oil. 

Ginger oleoresin is obtained by solvent extraction of dried ginger and is prepared both in certain industrialized Western countries and in some of the spice-producing... 

Ginger oleoresin was extracted from rhizomes with ethanol, isopropanol or liquid carbon dioxide. All oleoresin samples had monoter-penes and sesquiterpenes. Carboxylic acids were found in organic solvent extracts for an extraction time of 2h. The components responsible for the pungent characteristic of the oleoresin gingerols were detected in... 

The cinnamon of commerce is the dried inner bark of the tree, C. vemm. ft is an essential item in curry powders and masalas. The bark oil, bark oleoresin and leaf oil are important value-added products from cinnamon. Bark oil is used in the food and pharmaceutical industries. Cinnamon leaf oil is cheaper than bark oil and is used in the flavour industry. Cinnamon oleoresin, obtained by solvent extraction of the bark, is used mainly for flavouring food products such as cakes and confectionary. As in the case of cinnamon, the volatile oil and oleoresin from cassia are also used extensively in flavouring, especially soft drinks and other beverages. 

The oleoresin, prepared by solvent extraction of the spice, is prepared on a relatively small scale in Russia and in some Western countries. 

Coriander oleoresin is prepared by solvent extraction of the spice. The oleoresin contains the volatile oil, fatty oil and some other extractives, but their relative abundance is dependent on the raw material, the processing procedure and the particular solvent used. Coriander oleoresins commonly contain about 90% fatty oil and about 5% steam-volatile oil. 

Fennel oleoresin is prepared by solvent extraction of whole seeds and normally contains a volatile oil of 50% or a guaranteed content in the range of 52-58%. Only small quantities are produced for specific uses as it is not a substitute for fennel oil. Chemical analysis by Barazani et al. (2002) of the volatile fraction of oleoresins from fruits of seven natural populations of F. vulgare var. vulgare (bitter fennel) from the wild and after cultivation indicated the presence of two groups of populations. Chemotypic differentiation (relative contents of estragole and trans-anethole) or phenotypic plasticity increases within-species chemical variability, but the specific ecological roles of these essential oils remain to be uncovered. 

Vanilla is available in three physical forms, whole beans, splits and cuts. Vanilla powder is a mixture of ground vanilla in a carrier such as 30% sugar (Purseglove et al., 1981). Vanilla extract is made by cutting the cured beans into small pieces and percolating in successive quantities of hot 65—70% alcohol. The extract is very concentrated, a few drops sufficing for most uses. Vanilla oleoresin involves solvent extraction of chopped beans and later evaporation of the vanilla extract under vacuum, leaving a dark, viscous mass (Cowley, 1973). The oleoresin is diluted with... 

Increases in yield of naval stores are brought about by chemical treatment of the exposed wood, especially with paraquat herbicides (dipyridyl compounds). This treatment stimulates extensive oleoresin formation and diffusion into the wood, extending to the pith of the tree and several feet above the treatment level. As much as 40 percent oleoresin content in the wood has been produced. Such treatment could double naval stores production, for both gum and sulfate processes. It also has the potential of providing a new type of wood naval stores by solvent extraction prior to kraft pulping, or a combination of both methods. 

Oleoresin Angelica Seed Obtained by the solvent extraction of the dried seed of Angelica archangelica L. (Fam. Umbellif-erae) as a dark brown or green liquid. 

Oleoresin Black Pepper Obtained by the solvent extraction of the dried fruit of Piper nigrum L. (Fam. Piperaceae) as a dark green, olive green, or olive drab extract usually consisting of an upper oily layer and a lower crystalline layer. It may appear as a homogeneous emulsion if examined shortly after the oleoresin has been homogenized, but the product separates on standing. It may be decolorized by partial removal of chlorophyll. 

Oleoresin Capsicum Obtained by the solvent extraction of dried pods of Capsicum frutescens L. or Capsicum annum L. (Fam. Solanaceae) as a clear red to dark red, somewhat viscous liquid of characteristic odor, flavor, and bite. It may be decolorized through good manufacturing practices. It is partly soluble in alcohol (with oily separation and/or sediment) and is soluble in most fixed oils. The bite is usually standardized according to the label declaration. 

Oleoresin Fennel Obtained by the solvent extraction of the dried fruit of Foeniculum vulgare P. Miller (Fam. Umbelliferae) as a brown-green liquid. 

Oleoresin Pimenta Berries Obtained by the solvent extraction of the dried fruit of Pimenta officinalis Lindl (Fam Myrtaceae) as a brown-green to dark green liquid. Oleoresin Rosemary Obtained by the solvent extraction of the dried leaves of Rosmarinus officinalis L. (Fam. Labiatae). It is a thick, green paste that can be diluted with food-grade water- or oil-dispersible solvents. It may have a reduced chlorophyll content. The volatile oil content varies depending on its intended effect from a highly camphoraceous note to a subtle herbal note. 

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