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Identification and changes of flavonoids in Merlot and Cabernet Sauvignon wines. J Food Sci

Authors Wulf and Nagel are with the Dept. of Food Science & Technology, Washington State Univ., Pullman, WA 99164.
Journal of Food Science (Impact Factor: 1.79). 08/2006; 45(3):479 - 484. DOI: 10.1111/j.1365-2621.1980.tb04080.x

ABSTRACT Twenty components of an ethyl acetate extract from Merlot and Cabernet Sauvignon wines were isolated by recycle preparative HPLC. A combination of paper chromatography, fluorescence behavior, gas chromatography, reaction with molybdate, reaction with vanillin/HCI, ultraviolet spectrometry and mass spectrometry was used to gain information about the identities of the isolated compounds. Seven of the isolated compounds were catechins, procyanidins or degradation products thereof. Three flavonol glycosides were isolated and one was characterized as an isorhamnetin-3-glycoside. Four compounds were isolated with identical molecular weights and an uncharacteristic blue reaction with vanillin/HCl. These components were interconvertable and thought to be cis-trans isomers of flavenes. The changes in these components during aging of Merlot and Cabernet Sauvignon wines are discussed.

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    • "In order to characterize the products of degradation of ANC owing to industrial treatment of juices, further experiments with NaHSO 3 (Somers & Evans, 1977; Wulf & Nagel, 1980; Glories, 1984; Azar et al., 1987) were attempted. NaHSO 3 allowed the degree of degradation of the pigments and of the quantity of polymers to be estimated by comparison of OD 520 before and after the action of an aqueous solution of NaHSO 3 (50% v/v) on the different juices FPJ, RJ and SJ. "
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    International Journal of Food Science & Technology 12/2001; 35(3):275 - 283. DOI:10.1046/j.1365-2621.2000.00330.x · 1.35 Impact Factor
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    • "grapes, mainly in the skin (Wulf and Nagel, 1980; Cheynier and Rigaud, 1986) in the monoglycoside form, with the sugar residue linked to the hydroxyl group mainly in position C-3 of the O-containing ring. "
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