Oleoresins

Many spices are processed (2) to produce essential oils, oleoresins, essences, tinctures, extracts, resinoids, etc. These processes separate nonflavor components and further concentrate the aromatic or pungent principles of the spices. Such products allow a wider variety of uses and appHcations of the vital spice components. 

United States Imports of Spices and Oleoresins. The consumption of spices has continued to increase in the United States into 1993 (7). The demand for ethnic foods, and the trend toward less salt, glycerides, and fat, has stimulated more spice and condiment use. The United States consumes approximately 25% of the spices produced in the world. In 1993, imports accounted for about 65% of U.S. seasoning needs compared to 80% in the early 1980s. In 1991 approximately 50% by value of U.S. imported spices entered New York, the principal port of entry around 1983 more than 75% was imported through this port. The volume of spices and oleoresins (spice extracts) into the United States has been increasing steadily, but the value of imports has varied because of specific shortages and large price variations (Table 1). 

Table 1. United States Spice and Oleoresin Imports ...

U.S. Oleoresin Imports. Reports of the USDA Hst only paprika and black pepper oleoresins by name, and label all others, eg, capsicum, celery seed, and turmeric, as "other" (Table 3). The steady increase in the value of oleoresin imports is expected to continue. 

United States Exports of Spices and Oleoresins. The United States (ca 1993) is the foremost grower of peppermint, spearmint, orange, lemon, lime, and grapefmit products. The mints are processed to essential oils, and the citms fmit are sold as fresh fmit or processed to fro2en... 

Information regarding U.S. production of oleoresins is not available. It is estimated that there is a decline in domestic production of oleoresins of those spices imported in large volume, such as black pepper, capsicums of all types, and turmeric, since these oleoresins are more frequendy produced in the growing areas. However, the manufacture of specialty oleoresins produced from selected imports will continue, and oleoresin production from domestically grown spices is expected to increase (7,8). 

The FDA has pubhshed methods for the deterrnination of residual solvents in spice extracts such as oleoresins and has limited the concentrations of those specific solvents that are permitted. Chlorinated hydrocarbons and benzene have been almost completely removed from use as extracting solvents in the United States their use continues overseas where toxicity regulations are less stringent. The presence of pesticides or herbicides in spices is rigidly controHed by the FDA. 

Types of internal enamel for food containers include oleoresins, vinyl, acryflc, phenoHc, and epoxy—phenoHc. Historically can lacquers were based on oleoresinous products. PhenoHc resins have limited flexibiHty and high bake requirements, but are used on three-piece cans where flexibiHty is not required. Vinyl coatings are based on copolymers of vinyl chloride and vinyl acetate dissolved in ketonic solvents. These can be blended with alkyd, epoxy, and phenoHc resins to enhance performance. FlexibiHty allows them to be used for caps and closures as weU as drawn cans. Their principal disadvantage is high sensitivity to heat and retorting processes this restricts their appHcation to cans which are hot filled, and to beer and beverage products. 

Chemical iajections iato piae trees have been reported to have stimulatory effects on the natural production of resias and terpenes and may result ia high yields of these valuable chemicals. Combiaed oleoresin—timber production ia mixed stands of piae and timber trees is under development, and it appears that when short-rotation forestry is used, the yields of energy products and timber can be substantially higher than the yields from separate operations. 

Plastics. Vehicles in offset inks for plastics (polyethylene, polystyrene, vinyl) are based on hard drying oleoresinous varnishes which sometimes are diluted with hydrocarbon solvents. Letterset inks for polystyrene employ vehicles of somewhat more polar nature. Polyester or other synthetic resins (acryhc) dissolved in glycol ethers and/or esters are used in some of the older inks. Uv inks are widely used for decoration of these preformed plastic containers. 

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. 

Resin and Resinoid. Natural resins are plant exudates formed by the oxidation of terpenes. Many are acids or acid anhydrides. Prepared resins are made from oleoresins from which the essential oil has been removed. A resinoid is prepared by hydrocarbon extraction of a natural resin. 

Substituted heat-reactive resins are most widely used in contact-adhesive appHcations and, to a lesser extent, in coatings (77,78) -butylphenol, cresol, and nonylphenol are most frequendy used. The alkyl group increases compatibiHty with oleoresinous varnishes and alkyds. In combination with these resins, phenoHcs reduce water sensitivity. Common appHcations include baked-on and electrical insulation varnishes, and as modifiers for baking alkyds, rosin, and ester gum systems. Substituted heat-reactive resins are not used for air-dry coatings because of theh soft, tacky nature in the uncured state substituted nonheat-reactive phenoHcs are the modifying resin of choice in this case. 

Substituted nonheat-reactive resins do not form a film and are not reactive by themselves, but are exceUent modifier resins for oleoresinous varnishes and alkyds. Thein high glass-transition temperature and molecular weight provide initial hardness and reduce tack oxygen-initiated cross-linking reactions take place with the unsaturated oils. 

PhenoHcs that are not heat-reactive may be incorporated into both air-dried and baked oleoresinous coatings. AppHcations vary widely and include clear and pigmented exterior varnishes, aluminum-maintenance paints, 2inc-rich primers, can coatings, insulation varnishes, and concrete paints. As modifiers in a great variety of appHcations, they enhance the performance of oleoresinous and alkyd coatings. 

Dog repeUents available commercially in the 1990s have been generally unsuccessful in laboratory tests. Por example, lithium chloride treatments were usually rejected immediately with no ingestion, and bone oil treatments that contained up to 0.1% of the active ingredient were stiH consumed (93). Oleoresin capsicum [8023-77-6], the essence of red pepper, did have an extended effect on coyotes, even though the deer repeUents mentioned above were attractive to coyotes (93). Although a capsicum-base aerosol repeUent has been described as potentially harmful (94), pepper spray is commercially available in the United States to repel humans, as is Mace. 

In the gum rosin process, pine trees are wounded to stimulate the flow of gum. V-shaped slashes are cut through the bark, and the exudate is collected in a bucket below the slash. Production is stimulated by painting sulfuric acid on the slashes. The oleoresin (exudate) is separated by distillation into gum spidts of turpentine and gum rosin. The gum turpentine industry has decreased in importance in the 1990s because it is labor-intensive. The process is carried out in Russia, the People s Repubflc of China, Indonesia, Portugal, Brazil, and Mexico. 

Terpenes are found as constituents of essential oils and oleoresins of plants. Since antiquity they have been isolated and used in flavor and fragrance apphcations. Many important constituents of the essential oils have been identified and syntheses for them developed (see Oils, essential). 

Trichloroethylene was approved for use for many years as an extraction solvent for foods. In late 1977, the Eood and Dmg Administration (EDA) harmed its use as a food additive, direcdy or indirecdy, prohibiting the use in hop extraction, decaffeination of coffee, isolation of spice oleoresins, and other apphcations. The EDA also harmed the use of trichloroethylene in cosmetic and dmg products (23). 

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