title: Impact of Fluorescent Lighting on Oxidation of Model Wine Solutions Containing Organic Acids and Iron.
abstract: Previous studies have provided evidence that light exposure can increase oxygen consumption in wine and that the photodegradation of iron(III) tartrate could contribute to this process. In the present study, model wine solutions containing iron(III) and various organic acids, either alone or combined, were stored in sealed clear glass wine bottles and exposed to light from fluorescent lamps. Dissolved oxygen was monitored, and afterward the organic acid degradation products were determined and the capacity of the solutions to bind sulfur dioxide, the main wine preservative, was assessed. In the dark controls, little or no dissolved oxygen was consumed and the organic acids were stable. In the irradiated solutions, dissolved oxygen was consumed at a rate that was dependent on the specific organic acid present, and the latter were oxidized to various carbonyl compounds. For the solutions containing tartaric acid, malic acid, and/or citric acid, irradiation increased their sulfur dioxide-binding capacity.
authors.affiliation: National Wine and Grape Industry Centre, School of Agricultural and Wine Sciences, Charles Sturt University , Locked Bag 588, Wagga Wagga, New South Wales 2678, Australia.
authors.forename: Paris
authors.identifier: http://orcid.org/0000-0001-6549-5591
authors.initials: P
authors.lastname: Grant-Preece
authors.affiliation: National Wine and Grape Industry Centre, School of Agricultural and Wine Sciences, Charles Sturt University , Locked Bag 588, Wagga Wagga, New South Wales 2678, Australia.
authors.forename: Celia
authors.initials: C
authors.lastname: Barril
authors.affiliation: National Wine and Grape Industry Centre, School of Agricultural and Wine Sciences, Charles Sturt University , Locked Bag 588, Wagga Wagga, New South Wales 2678, Australia.
authors.forename: Leigh M
authors.initials: LM
authors.lastname: Schmidtke
authors.affiliation: National Wine and Grape Industry Centre, School of Agricultural and Wine Sciences, Charles Sturt University , Locked Bag 588, Wagga Wagga, New South Wales 2678, Australia.
authors.forename: Andrew C
authors.identifier: http://orcid.org/0000-0002-3719-9995
authors.initials: AC
authors.lastname: Clark
mesh_terms: D000143:Acids / Q000737:chemistry*; D005453:Fluorescence; D007501:Iron / Q000737:chemistry*; D008027:Light; D010084:Oxidation-Reduction / Q000528:radiation effects; D014920:Wine / Q000032:analysis* / Q000528:radiation effects*
chemical_list: D000143:Acids; D007501:Iron
keywords: glyoxylic acid; iron(III) carboxylate; lactic acid; photo-Fenton; photochemistry; succinic acid