Τίτλος:
Measuring protection of aromatic wine thiols from oxidation by competitive reactions vs wine preservatives with ortho-quinones
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
Quinones are central intermediates in wine oxidation that can degrade the quality of wine by reactions with varietal thiols, such as 3-sulfanylhexanol, decreasing desirable aroma. Protection by wine preservatives (sulphur dioxide, glutathione, ascorbic acid and model tannin, phloroglucinol) was assessed by competitive sacrificial reactions with 4-methyl-1,2-benzoquinone, quantifying products and ratios by HPLC-UV-MS. Regioselectivity was assessed by product isolation and identification by NMR spectroscopy. Nucleophilic addition reactions compete with two electron reduction of quinones by sulphur dioxide or ascorbic acid, and both routes serve as effective quenching pathways, but minor secondary products from coupled redox reactions between the products and reactants are also observed. The wine preservatives were all highly reactive and thus all very protective against 3-sulfanylhexanol loss to the quinone, but showed only additive antioxidant effects. Confirmation of these reaction rates and pathways in wine is needed to assess the actual protective action of each tested preservative. © 2014 Elsevier Ltd. All rights reserved.
Συγγραφείς:
Nikolantonaki, M.
Magiatis, P.
Waterhouse, A.L.
Περιοδικό:
Food Chemistry
Εκδότης:
Elsevier Ireland Ltd
Λέξεις-κλειδιά:
Addition reactions; Antioxidants; Ascorbic acid; Nuclear magnetic resonance spectroscopy; Nucleophiles; Oxidation; Peptides; Quinone; Reaction rates; Reactivity (nuclear); Redox reactions; Sulfur determination; Sulfur dioxide; Wine, Antioxidant effect; Competitive reactions; Glutathiones; Nucleophilic additions; Product isolation; Protective action; Secondary product; Two-electron reduction, Reaction intermediates, ascorbic acid; food preservative; glutathione; phloroglucinol; quinone derivative; sulfur dioxide; tannin; thiol derivative; 4-methyl-1,2-benzoquinone; antioxidant; benzoquinone derivative; food preservative; thiol derivative, article; carbon nuclear magnetic resonance; controlled study; electrophilicity; electrospray mass spectrometry; heteronuclear multiple bond correlation; limit of quantitation; nuclear magnetic resonance spectroscopy; nucleophilicity; oxidation reduction reaction; proton nuclear magnetic resonance; reversed phase liquid chromatography; synthesis; wine; analysis; chemistry; comparative study; high performance liquid chromatography; mass spectrometry; oxidation reduction reaction; procedures; wine, Antioxidants; Benzoquinones; Chromatography, High Pressure Liquid; Food Preservatives; Mass Spectrometry; Oxidation-Reduction; Sulfhydryl Compounds; Wine
DOI:
10.1016/j.foodchem.2014.04.079
