Headspace analysis theory

Shahidi, F. In Headspace Analysis of Foods and Flavors. Theory and Practice-, Rouseff, R.L. Cadwallader, K.R., Eds. Kluwer academic New York, 2001, pp 113-123. 

The volatile nature of ethanol makes it eminently suitable for headspace analysis. The principle on which the method is based is that of partition theory, i.e., that the concentration of a volatile species in the headspace above a solution is proportional to the concentration of that species in solution. Procedures based on this principle must therefore be classed as indirect , but nevertheless they have some advantages over direct methods, the most important being that the procedure separates volatile species from the numerous nonvolatile compounds commonly found in alcoholic beverages. As most sensors used in instrumentation for the determination of ethanol are at best semispecific and are usually oxidative in... 

See also Air Analysis Sampling. Chromatography Overview Principles. Clinical Analysis Sample Handling. Drug Metabolism Metabolite Isolation and Identification. Extraction Solid-Phase Extraction. Food and Nutritional Analysis Sample Preparation. Forensic Sciences Volatile Substances. Headspace Analysis Purge and Trap. Perfumes. Sample Handling Sample Preservation Automated Sample Preparation. Sampling Theory. 

See also Extraction Solvent Extraction Principles Solid-Phase Extraction. Fluorescence Environmental Applications. Gas Chromatography Mass Spectrometry Environmental Applications. Gravimetry. Headspace Analysis Static Purge and Trap. Immunoassays Overview. Infrared Spectroscopy Overview. Liquid Chromatography Overview. Sampling Theory. 

In Chapter 3 Ulberth outlines the theory and practice of static headspace gas chromatography. He then considers the analysis of volatile lipids in the study of the digestive tract and in nutritional physiology. Equally important is the contribution headspace analysis can make in the study of oxidative rancidity. Ulberth contrasts static headspace gas chromatography with dynamic headspace analysis. 

J Pawliszyn. Solid phase microextraction. In RL Rouseff, KR Cadwallader, eds. Headspace Analysis of Foods and Flavors Theory and Practice. New York Kluwer Academic/Plenum Publishers, 2001, pp 73-87. 

Theory of chromatography column efficiency expanded Chromatography simulation software for method development Capillary gas chromatography (GC) columns updated and expanded Headspace, thermal desorption, and purge and trap GC analysis Fast gas and hquid chromatography... 

A series of headspace analyses is carried out on the same sample, which is conditioned to equilibrium between each analysis step. From the progressive, measured decrease in concentrations determined, the analyte concentration in the original sample can be calculated. The theory is outlined below. 

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