Phenolic compounds in foods

Optimising the use of phenolic compounds in foods 317 16.1.2 Classifying natural antioxidants... 

Knowledge of the identity of phenolic compounds in food facilitates the analysis and discussion of potential antioxidant effects. Thus studies of phenolic compounds as antioxidants in food should usually by accompanied by the identification and quantification of the phenols. Reversed-phase HPLC combined with UV-VIS or electrochemical detection is the most common method for quantification of individual flavonoids and phenolic acids in foods (Merken and Beecher, 2000 Mattila and Kumpulainen, 2002), whereas HPLC combined with mass spectrometry has been used for identification of phenolic compounds (Justesen et al, 1998). Normal-phase HPLC combined with mass spectrometry has been used to identify monomeric and dimeric proanthocyanidins (Lazarus et al, 1999). Flavonoids are usually quantified as aglycones by HPLC, and samples containing flavonoid glycosides are therefore hydrolysed before analysis (Nuutila et al, 2002). 

Escarpa A and Gonzalez MC. 2001. An overview of analytical chemistry of phenolic compounds in foods. Crit Rev Anal Chem 31 57-139. 

Harnly JM, Bhagwat S and Lin LZ. 2007. Profiling methods for the determination of phenolic compounds in foods and dietary supplements. Anal Bioanal Chem 389(1 ) 47—61. 

Leighton, T. et al.. Molecular characterization of quercetin and quercetin glycosides in Allium vegetables their effects on malignant cell transformation. In Huang, M.T., Ho, C.T., and Lee, C.Y., eds.. Phenolic Compounds in Food and their Effects on Health II. Antioxidants and Cancer Prevention. New York American Chemical Society, 1992, p. 220. 

Tonnesen, H.H., Chemistry of curcumin and curcuminoids, in Phenolic Compounds in Foods and their Effects on Health. 1 Analysis, Occurrence and Chemistry, Ho, C.-T., Lee, C.Y., and Huang, M.-T., Eds., American Chemical Society, Washington, DC, 1992. 

Huang, M.-T. and Ferraro, T. 1992. Phenolic compounds in food and cancer prevention. In Phenolic Compounds in Food and Their Effects on Health II Antioxidants and Cancer Prevention (M.-T. Huang, C.-T. Ho, and C.Y. Lee, eds.), American Chemical Society Symposium Series 507, pp. 8-34. ACS, Washington, D.C. 

Numerous papers have relied on only UV-visible spectra for their identification of phenolics, but for positive identification purposes, HPLC-mass spectrometry (MS) is another detection mode that can provide detection of all phenolic compounds in foods. This technique involves a hyphenated instrument that uses a mass spectrometer as a detector for HPLC or uses HPLC as cleanup step for mass spectrometry. After preparative HPLC, the MS technique has frequently been employed for structural identification of phenolics in many foods and essential oils because of its sensitivity and selectivity and its ability to provide structural information. 

Prochaska, HJ, Talalay P. 1992. Phenolic antioxidants as inducers of anticarcinogenic enzymes. In Huang, M-T, Ho C-T, Lee CY, eds. Phenolic compounds in food and their effects on health. Vol. II. 150-159. American Chemical Society Symposium Series No. 507. 

A. L. Khurana, in Phenolic Compounds in Food and Their Effects on Health (Eds. C.-T. Ho,... 

Maga J.A. (1978a) Simple phenol and phenolic compounds in food flavor. CRC Crit Rev Food Teclmol. 10, 323-72. 

Lee, C.Y. In ACS Symposium Series. Phenolic Compounds in Food and their... 

Tonnesen, H. H. In Phenolic Compounds in Food and Their Effects on Health I- Analysis, Occurance. and Chemistry Editor, Ho, C.-T. Lee, C. Y., and Huang, M-T, ACS Symposium Series 507, American Chemical Society Washington, DC, 1992 pp. 144-153. 

Hughes, L. Burton, G. W. Ingold, K. U. Slaby, M. Foster, D. O., Phenolic Compounds in Food and Their Effects on Health 11, ACS Symposiiiiit. Scries 507 American Chemical Society Washington, DC, 1992, Clwpter 14, pp 184-199. 

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