Phosphorus Derivatization as a Tool to Enhance Specificity of Quantitative NMR Analysis of Foods
The present contribution describes the application of a phosphorus-derivatization methodology that allows the use of 31P NMR spectroscopy for the determination of minor chemical components in foods. The specificity of the experimental protocol toward hydroxyl- and carboxyl-containing chemical compounds, such as mono- and diglycerides, phenolic compounds, terpenes, etc., allows the facile quantitative determination of these important compounds as minor components in complex food matrices. The glyceride and phenolic profiles obtained using the 31P-tagging NMR methodology are used in combination with 1H NMR data for the quality control and authentication of extra-virgin olive oil and other vegetable oils, but the specificity of this methodology allows it to be easily extended to more diverse foods and food products, that contain phenolic and/or bioactive compounds or other important minor components of analytical interest.
KeywordsNMR spectroscopy Olive oil Vegetable oils Phenolics Terpenic acids Food Chemical derivatization Plant extracts
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