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In recent years, several countries have implemented new regulations regarding the limitation or labeling of the trans fatty acid (TFA) content of foods and dietary supplements. GC methods for fatty acid (FA) analysis have been updated by improving the separation of TFAs from other FAs, especially trans- and cis-18:1, and by focusing more attention on the FAs contained in fats and oils in lower amounts. FA analysis is affected by the limited availability of reference materials. Identifications are frequently made simply by comparison with separations reported in the literature. This report describes the preparation of mixtures containing fatty acid methyl esters (FAMEs) that are not available as reference materials. These mixtures can be used for FAME identifications. The prepared mixtures are analyzed under the experimental conditions of the American Oil Chemists' Society (AOCS) Official Method Ce 1h-05 and AOCS Recommended Practice Ce 1j-07.

A rapid tool for evaluating authenticity was developed and applied to the screening of extra virgin olive oil (EVOO) retail products by using Fourier-transform near infrared (FT-NIR) spectroscopy in combination with univariate and multivariate data analysis methods. Using disposable glass tubes, spectra for 62 reference EVOO, 10 edible oil adulterants, 20 blends consisting of EVOO spiked with adulterants, 88 retail EVOO products and other test samples were rapidly measured in the transmission mode without any sample preparation. The univariate conformity index (CI) and the multivariate supervised soft independent modeling of class analogy (SIMCA) classification tool were used to analyze the various olive oil products which were tested for authenticity against a library of reference EVOO. Better discrimination between the authentic EVOO and some commercial EVOO products was observed with SIMCA than with CI analysis. Approximately 61% of all EVOO commercial products were flagged by SIMCA analysis, suggesting that further analysis be performed to identify quality issues and/or potential adulterants. Due to its simplicity and speed, FT-NIR spectroscopy in combination with multivariate data analysis can be used as a complementary tool to conventional official methods of analysis to rapidly flag EVOO products that may not belong to the class of authentic EVOO.

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