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2. Versari A., Boulton R.B., Parpinello G.P. (2008) A comparison of analytical methods formeasuring the color components of red wine. Food Chemistry, 106, 1, 397–402.The monomeric and polymeric pigments of 20 young red wines were analysed using most recent of theapproaches available for phenolics measurements in wine, including: (i) HPLC with silica-based reversed-phase,(ii) HPLC with polymeric-based reversed-phase columns, (iii) the spectrophotometric Adams’ tannin andpolymeric pigments assay, (iv) the Boulton’s copigmentation assay, and (v) the Somers’ unbleached polymericcolor assay. Moreover, a modification of an existing HPLC method, i.e. the addition of SO 2 to the mobile phases,allowed the unbleached polymeric pigments to be analysed by HPLC for the first time. The wines displayed avariation in their color density at 520 nm that ranged by 10-fold, and included wines made from Pinot noir,Merlot, Cabernet sauvignon, Cabernet franc, Sangiovese, Cagnulari and Cannonau grapes. The total color ofwines was an aggregate number of three components: copigmentation (8–30%), total free anthocyanins (24–35%), and polymeric pigment (35–63%). Cross-comparison between the selected method was performed anddiscussed. In particular, the polymeric pigments estimated by HPLC with polymeric-based reversed-phasecolumn were in good agreement with the result of the reversed-phase C 18 column (R 2 = 0.9703) and the sum ofsmall and large polymeric pigments estimated by the Adams’ assay (R 2 = 0.9511). The level of copigmentationcan be almost completely described by the levels of monomeric pigments (R 2 = 0.9464) and not by the tannincontent as has often been suggested (copigmentation vs tannin: R 2 = 0.4827).3. Versari A, Boulton RB, Parpinello GP (2007) Analysis of SO 2 -resistant polymeric pigmentsin red wines by high performance liquid chromatography. Am J Enol.Viticul 58: 523–525.A simple modification, the addition of SO 2 to the mobile phases, to an existing HPLC method for the analysis ofunbleached polymeric pigments in red wines using a silica-based polymeric column is described for the firsttime. The samples included wines made from Pinot noir, Merlot, Cabernet Sauvignon, Cabernet franc,Sangiovese, Cagnulari, and Cannonau grapes, mostly from the 2001 season, which covered a range of wine colorfrom 0.1 to 10 absorbance units at 520 nm. Results were compared to the level of SO 2 -resistant polymericpigments as measured by an existing spectrophotometric assay (R 2 = 0.992). In these wines, the ratio of the colorof the bleached polymeric pigments to that of the unbleached polymers averaged 0.19 with a coefficient ofvariation of 34%. The SO 2 -resistant polymeric pigments estimated by this HPLC method are also in goodagreement with those quantified by the protein precipitation spectrophotometric method of Harbertson andAdams (R 2 = 0.950).4. Versari A., Parpinello G.P., Mattioli A.U. (2007) Characterization of polymeric pigments andcolor components of commercial red wines by using selected UV-Vis spectrophotometricmethods. South African Journal of Enology and Viticulture, 28, 1, 6–10.The composition of the colour components of commercial red wines from Italy was analysed in terms of totalcolour, co-pigmentation, SO 2 -resistant pigments, small and large polymeric pigments, and tannins. A total of 128wines, including Sangiovese, Cabernet Sauvignon, Nero d’Avola, Merlot, Marzemino, Negroamaro, Aglianico,Cannonau and Rossese di dolceacqua from five vintages (1999 to 2003) were analysed. The composition of thewines showed significant differences in terms of total colour and co-pigmentation. Total colour at 520 nm washighest in Marzemino (7.50±1.5 AU, absorbance units), and then in Aglianico (7.10±2.8 AU) and CabernetSauvignon (5.01±2.50 AU). The level of large and small polymeric pigments in Sangiovese wines showed arange from 0.05 to 0.40 and 0.10 to 0.27 AU 520 nm, respectively. The variation in the level of polymericpigments is affected by a number of factors, including vintage, grape composition, fermentation and storageconditions.5. Versari A., Boulton R.B., Parpinello G.P. (2006) Effect of spectral pre-processing methods onthe evaluation of the color components of red wines using Fourier-Transform Infraredspectroscopy, Italian Journal of Food Science, 4, 18, 423–432.A rapid method for measuring the (i) free anthocyanins, (ii) copigmented anthocyanins, (iii) polymeric pigmentfractions and (iv) actual red color at 520 nm from the Fourier transform infrared (FTIR) spectrum was evaluated.Twenty wines, mostly one-year old, with red color ranging from almost zero to 10 absorbance units (AU) at 520nm were analyzed by reference methods for their levels of the selected color components. Partial least squares(PLS) regression, obtained from several spectral data preprocessing methods, was used for multivariatecalibration to relate the chemical variables to the FTIR spectra. The performance of different models wasSISTAL - SOCIETA’ ITALIANA DI SCIENZE E TECNOLOGIE ALIMENTARIDipartimento di Scienze e Tecnologie Agroalimentari, Università degli Studi della TusciaVia San Camillo de Lellis, 01100 ViterboTel.: 0761- 35 74 94/7 , Fax: 0761- 35 74 98, e-mail: mmoresi@unitus.it66