Oleoresin from spices

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. 

Enough groundwork on the generic nature of solubility behavior in SCF solvents has been developed in the previous chapters of this book for the reader to extrapolate from the idealized situation of separating a mixture of naphthalene and chalk dust to other, more practical systems. Other systems may include the extraction of oleoresins from spices where the desired product is the extract, or the extraction of monomers and oligomers from polymers where the desired product is the purified polymer, or the separation of a mixture of chemicals where both streams are valuable products. Many of these examples are enumerated in the following chapters. 

George, K.M., On the extraction of oleoresin from turmeric comparative performance of ethanol, acetone and ethylene dichloride, Indian Spices, 18, 7, 1981. 

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. 

Sankarikutty, B., Sumathykutty, M.A., Bhat, A.V. and Mathew, A.C. (1978) Studies on extractions of oils and oleoresins from cumin, fennel and fenugreek. Indian Arecanut, Spices and Cocoa Journal 2(2), 25-30. 

Spice Oleoresins used in foods are derived from spices and contain the total sapid, odorous, and related characterizing principles normally associated with the respective spices. The oleoresins are produced by one of the following processes (1) by extraction of the spice with any suitable solvent or solvents, in combination or sequence, followed by removal of the solvent or solvents in conformance with applicable residual solvent regulations (see General Requirements below) or (2) by removal of the volatile portion of the spice by distillation, followed by extraction of the nonvolatile portion, which after solvent removal, is combined with the total volatile portion. 

Usage Apart from the oleoresin, for spice extracts. 

Separation of miscella from extracted material and removal of solvent. The stripping of solvent from the desired extractives is critically important to the character and flavoring quality of the resulting oleoresin. Many spices contain highly volatile constituents so that the removal of solvent must be carried out under low temperature conditions so as to avoid loss or damage of these. The use of high vacuum is indicated but this can also... 

Rehm, H.-J. Industrielle Mikrobiologie. 2nd. edn.. Springer-Verlag Berlin. 1980 Risch, S.J., Ho, C.-T Spices. Flavor chemistry and antioxidant properties. ACS Symposium Ser. 660, American Chemical Society, Washington DC, 1996 Salzer, U.-J. The analysis of essential oils and extracts (oleoresins) from seasonings - a critical review. Crit. Rev. Food. Sd. Nutr. 9,345 (1977)... 

Lipid fractions (oleoresins), in which the monoglyceride content is somewhat higher (up to 2-3 wt%), have been explored and used for some applications. Many of the oleoresins extracted from fruits, flowers, spices, leaves, etc. consist of various triglycerides, nonsaponifiable fats (waxes), and monoglyceride derivatives. These fractions are sometimes self-emulsifiable and can form in situ water-in-oil emulsions. Such oleoresins from tomato, rosemary, sage, paprika, etc. can provide other functional properties. 

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. 

Pepper oil and pepper oleoresin are obtained from the black pepper Piper nigrum L. (Piperaceae). Pepper oil is produced by steam distillation of whole or crushed fruits. The oil is an almost colorless to bluish-green liquid with a characteristic odor, reminiscent of pepper, but without the pungency of the spice. 

The world of aroma compounds is becoming more and more complex. In the early days people used aromatic products like fruit juices or fruit juice concentrates which were relatively weak and still close to the related foodstulf. Later, with more knowledge of separation techniques, infusions, extracts, oleoresins and absolutes ranging from weak to strong impact were used to impart aroma. Essential oils such as spice oils already had a very strong impact. Modern analytical technologies allowed the evaluation of the chemical compositions of extracts and essential oils, so that isolates either as powerful mixtures or even as single compounds could be obtained. 

Oleoresin is the total soluble extractive in a specified solvent. From the functional point, the best oleoresin is one which contains all the flavour components of the material contributing to aroma, taste, pungency and related sensory factors which, when diluted to the original concentration in the original material, truly recreates the sensory quality of the original spice. 

India is the global leader in value-added products of turmeric and exports. Value-added products from turmeric include cur-cuminoids, dehydrated turmeric powder, oils and oleoresin. Turmeric, like other spices, is available whole, as ground and as oleoresin. The institutional sector in the West buys ground turmeric and oleoresins, while in the industrial sector, whole dry turmeric is preferred. 

Identification The volatile oil distilled from an oleoresin is similar in its physical and chemical properties, including its infrared spectrum, to that distilled from the spice of the same origin. To obtain the volatile oil from the oleoresin, proceed as directed under Volatile Oil Content, Appendix VHI. Residual Solvent Chlorinated Hydrocarbons (total) Not more than 0.003% Acetone Not more than 0.003% Isopropanol Not more than 0.003% Methanol Not more than 0.005% Hexane Not more than 0.0025%. 

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