Supercritical fluid extraction foodstuffs

As with most chromatographic methods applied to solid samples, sample digestion and analyte extraction methods are all important. IC is finding application in the analysis of foodstuffs following sample preparation using such techniques as microwave digestion, supercritical fluid extraction, accelerated solvent extraction, and pyrohydrolysis. 

Markova, M.E., Uryash, V.F., Gruzdeva, A.E., Grishatova, N.V., Kokurina, N.Yu., and Uryash, A.V., Determination of water content in biological active additives for food prepared by supercritical fluid extraction. In. Biotechnology, Biodegradation, Water and Foodstuffs, Zaikov, G.E. and Krylova, L.P., Eds, NY Nova Sci. Publ. Inc., 2009,... 

SCF). This fluid does not any more have a free surface, that characterizes a liquid as opposed to a vapour, but may serve as a useful solvent just the same. Some substances that are gases at ambient conditions can be compressed by high pressures to become supercritical fluids and solvents, a well-known example being carbon dioxide, used extensively as an extractant for foodstuffs and pharmaceuticals. Some physical properties—the critical temperature Tc, pressure Pc, and density dc—of supercritical solvents are shown in Table 3.3. 

Extraction and separation processes are basic industrial operations applied in many areas with considerable economic relevance. Supercritical fluids, especially carbon dioxide, are of increasing interest for new separation processes in the fields of foodstuffs, cosmetics and pharmaceuticals. 

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