RT Journal Article SR Electronic T1 An Assay of Different Phenolic Fractions in Winesa JF American Journal of Enology and Viticulture JO Am J Enol Vitic. FD American Society for Enology and Viticulture SP 55 OP 58 DO 10.5344/ajev.1971.22.2.55 VO 22 IS 2 A1 C. Peri A1 C. Pompei YR 1971 UL http://www.ajevonline.org/content/22/2/55.abstract AB A method is suggested for the fractionation and the determination of phenolics in white wines.The concentration of nonflavonoid phenolics, non-tannin flavonoids and tannin phenolics may be evaluated by applying the Folin-Ciocalteu reaction to the fractions obtained by selective precipitation of flavonoids with formaldehyde and of tannin phenolics with cinchonine sulfate.Good reproducibility of results was obtained in analysis of white wines. Qualitative evidence is given of the selectivity of the two precipitations.