Automated identification of phenolics in plant-derived foods by using library search approach

Phenolic compounds may contribute to the organoleptic, commercial and nutritional characteristics of plant-derived food and beverages and their consumption has been associated with positive health benefits. Consequently, it is essential to determine the nature and distribution of these compounds in the diet. We have developed a reliable, reproducible, fast and sensitive method for the identification of phenolics using liquid chromatography interfaced to an ESI-Qq-TOF mass spectrometer, which provides mass accuracy and true isotopic pattern in MS and MS/MS. We built up a library of phenolic compounds using retention time, MS and MS/MS spectra. Fragmentation patterns in the negative ionisation mode are discussed. We have applied the automated library search in some of the components of a food supplement (propolis and lyophilisate of some vegetables) selected by its antioxidant properties. A variety of phenolic components was successfully identified.