title: The decay of ascorbic acid in a model wine system at low oxygen concentration.
abstract: The present study investigated the impact of temperature on the degradation of ascorbic acid in low oxygen conditions in a model white wine. The concentrations of ascorbic acid, furfural, sulfur dioxide and phenolic-type products were monitored in a model white wine stored under non-oxidative conditions at 45.0, 36.5 and 24.0 °C for up to 693 days. The concentrations of both ascorbic acid and sulfur dioxide decreased over the analysis period while furfural and other colourless phenolic products increased in concentration, despite the presence of residual sulfur dioxide. The decay of ascorbic acid in the low oxygen conditions followed first-order kinetics and the rate constants were determined to be (3.5±0.2)×10(-8), (1.02±0.07)×10(-8), and (0.184±0.009)×10(-8) s(-1) for 45.0, 36.5 and 24.0 °C (n=5, standard error), respectively, and the activation energy was 110±3 kJ/mol (n=3, standard error). Importantly, these data allow more accurate prediction of the temperature-induced loss of ascorbic acid in low oxygen conditions during transport or storage of wine.
authors.affiliation: National Wine and Grape Industry Centre, Charles Sturt University, Locked Bag 588, Wagga Wagga, NSW 2678, Australia.
authors.forename: Nadja
authors.initials: N
authors.lastname: Wallington
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Clark
authors.forename: Paul D
authors.initials: PD
authors.lastname: Prenzler
authors.forename: Celia
authors.initials: C
authors.lastname: Barril
authors.forename: Geoffrey R
authors.initials: GR
authors.lastname: Scollary
mesh_terms: D000975:Antioxidants / Q000737:chemistry; D001205:Ascorbic Acid / Q000737:chemistry*; D007700:Kinetics; D008954:Models, Biological; D010100:Oxygen / Q000032:analysis; D013696:Temperature; D014920:Wine / Q000032:analysis*
chemical_list: D000975:Antioxidants; D001205:Ascorbic Acid; D010100:Oxygen
keywords: Anaerobic; Ascorbic acid; Furfural; LC–MS; Non-oxidative; Sulfur dioxide; UHPLC; UV–Vis; Wine; high performance liquid chromatography with mass spectrometry detection; ultrahigh performance liquid chromatography; ultraviolet–visible.