Solvent oleoresins

High-pressure C02 extracts are, in many cases, superior to solvent oleoresins and essential oils when used as food flavourings and have significantly lower spice... 

Oleoresinous and solvent Oleoresinous and solvent Polyfunctional (acrylated) compounds Resin/solvent... 

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. 

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. 

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). 

Paprika oleoresin (EEC No. E 160c) is the combination of davor and color principles obtained by extracting paprika with any one or a combination of approved solvents acetone, ethyl alcohol, ethylene dichloride, hexane, isopropyl alcohol, methyl alcohol, methylene chloride, and trichloroethylene. Depending on their source, paprika oleoresins are brown—red, slightly viscous, homogeneous Hquids, pourable at room temperature, and containing 2—5% sediment. 

Preparation of carotenoid extract from plant oleoresin and hydrolysis with alkahne reagent in polar organic solvents (ether, polyhydroxyl alcohol, and ether alcohol)... 

For example, the lycopene available on the market is supplied mainly by LycoRed (www.lycored.com), a company that uses a classical extraction system (ethyl acetate as solvent) and maintains a monopoly position for lycopene production on a large scale. The manufacturing of the Lyc-O-Mato oleoresin (recognized by European Regulation 258/97/EC) product of LycoRed is almost identical to the production of the food additive and includes physical operations to separate the pulp from ripe tomatoes extracted according to GMPs and lSO-9002-certified procedures. The final product contains 6 to 15% lycopene the total lycopene recovery from pulp reaches 85% and from paste around 50%. 

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. 

Vanilla extract (vanilla oleoresin) is produced by extraction of the pods of Vanilla planifolia G. Jacks, or V. tahitensis Moore (Orchidaceae) with a polar solvent (e.g., methanol, ethanol, or acetone, which may also contain water). The composition of the extract depends on the type and amount of solvent used. Generally, the percentage of vanillin in the extract (yield 25-30%) is 3-4 times higher than that in the pods [807c, 807d]. 

Extracts of aromatic plant or animal materials obtained using organic solvents or fluidised gasses are not considered as essential oils [1, 23, 25-28]. Concretes, absolutes, spice oleoresins, etc. which can be classified as aromatic extracts are not covered in this chapter. 

In the United States, dichloromethane may be present as an extractant or process solvent residue in spice oleoresins at a level not to exceed 30 mg/kg [ppm] (including all chlorinated solvents), in hops extract at less than or equal to 2.2% and in coffee at a level not to exceed 10 mg/kg [ppm] (United States Food and Drug Administration, 1996). 

Most of the industrially applied separation processes use precipitation by means of reduced solvent power by changing the pressure/temperature in one or more steps. In most cases, as for the production of oleoresins from spices, or the extraction of hops, a single-step separation is sufficient. Double- or triple-step separations are applied for spice extraction, in case enrichment of pungency, colour or essential oils are desired - as, for example, with pepper, with precipitation of piperin, the pungent substance of the pepper, in the first step, and essential oil in the second step. 

One of the disadvantages of conventional oleoresins is their contamination with small amounts of organic solvent. Further, by removing this solvent under vacuum, a part of the initial original flavour is lost. 

There are a number of published applications in which spices are extracted with liquid carbon dioxide to isolate a flavour- or aroma concentrate [22,48,54], Liquid CO2 dissolves the essential oils and lighter fractions of the oleoresins. Supercritical CO2 is generally a better extracting-solvent than liquid CO2, because higher densities, equivalent to higher solubility, can be achieved by raising the pressure. 

The traditional extraction processes do not provide a method for selective fractionation of the oleoresin components. This fractionation must be carried out in additional processing steps, involving further use of organic solvents or costly processes such as molecular distillation. 

In the patent of the Krupp company [60], ground paprika and oleoresin may be used as the raw material in the SFE process. The solvent can be supercritical fluid carbon dioxide, ethane, ethylene, or a mixture of the last two. As modifiers ethanol, acetone, water, and mixtures of these solvents were proposed. 

The pure oleoresin produced by solvents normally contains only pure curcumin, in a crystalline form. It is hardly soluble in liquid- and supercritical CO2- Even at an extraction pressure of 450 bar, and with 2 hours extraction time at 65°C, only 20% of the initial curcumin can be extracted. On the other hand, all the volatile oil and fatty oil is extracted, and a fat-free curcumin-starch mixture with a very low flavour-content can be produced. The total extraction yields are between 5 to 12%, with mostly fatty oil and volatile oil, and about 10% curcumin in the extract. 

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