Chromatographic Methodologies: Compounds for Olive Oil Traceability Issues

  • Manuel León-Camacho
  • Maria T. Morales
  • Ramón Aparicio
Chapter

Abstract

any analytical methods have been proposed to characterize olive oil because of the numerous olive oil components. To organize such a heterogeneous group of methods, they have been clustered in accordance with the classical division of compounds into major and minor compounds and the unsaponifiable fraction. Thus, the methods for the group of major compounds are focused on the derivatization of fatty acids, the gas–liquid chromatography (GLC) of their methyl esters, the determination of trans fatty acids, and the main characteristics of the chromatographic techniques determining triacylglycerols, for example, columns, mobile phases, and detectors of HPLC and sample preparation, columns, injection systems, and detectors of GLC. The analytical methods and techniques for determining diacyl- and monoacylglycerols, free fatty acids, fatty acid alkyl esters, and waxes, among others, are described and analyzed with chromatograms in a section devoted to the ample and heterogenous set of minor components. The unsaponifiable matter clusters a set of natural or accidental constituents that fail to react with NaOH and KOH to produce soaps while remaining soluble in classic fat solvents (hexane, ether) after saponification. These compounds, which rarely represent more than 2 % of total olive oil composition, include many substances that are thought to be the olive oil fingerprint. Thus, a panoply of methods and techniques, some that are official standards and others that are in-house proposals, is analyzed and compared after describing the methodologies for unsaponifiable determination. The chapter also gives attention to methodologies and techniques designed for determining hydrocarbons that are present in olives or are a consequence of olive oil processing, such as squalene, n-alkanes, n-alkenes, and stigmastadienes, or resulting from external or inappropriate practices such as pesticides and polycyclic aromatic hydrocarbons. The methods for determining sterols (4-desmethylsterols, 4,4-dimethylsterols, and 4-monomethylsterols) are of special relevance because these compounds are related to olive oil authentication, varietal characterization, and identification of olive oil geographical origins, in addition to their importance as bioactive components. Finally, the chapter analyzes appropriate methods for the determination of a miscellany of compounds (e.g., tocopherols, sterols oxidation products, linear alcohols, triterpenic dialcohols) of interest in authentication, quality, and nutrition.

Keywords

HPLC Sulfuric Acid Dehydration Pyrene Volatility 

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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Manuel León-Camacho
    • 1
  • Maria T. Morales
    • 2
  • Ramón Aparicio
    • 1
  1. 1.Spanish National Research Council, Instituto de la Grasa (CSIC)SevillaSpain
  2. 2.Department of Analytical ChemistryUniversity of SevillaSevillaSpain

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