The phenolic chemistry and spectrochemistry of red sweet wine-making and oak-aging.
A natural sweet wine (NSW) was made with dried grapes from Vitis vinifera L. cv Garnacha Tintorera. A fortified sweet wine (FSW) was also obtained: the maceration-alcoholic fermentation of Garnacha Tintorera must was stopped by addition of ethanol 96% (v/v). UV/Vis spectrophotometry and HPLC/DAD-ESI/MS were applied to determine, respectively, the evolution of colour and phenolic compounds in Garnacha Tintorera based-sweet wines during aging. In sweet wines, aging decreased a(∗) (red/green), colour saturation and lightness and increased b(∗) (yellow/blue), and hue angle. Most of the phenolic compounds determined, such as anthocyanins, esters of hydroxycinnamic acids, flavan-3-ols monomers, oligomers and polymers decreased in both sweet wines during aging. On the contrary, hydroxybenzoic and hydroxycinnamic acids and vitisins increased after one year of aging. Despite that both terminal and extension subunit compositions show very small changes, mean degree of polymerisation of proanthocyanidins decline slightly as aging progressed in both sweet wines.
Nutrition and Bromatology Group, Analytical and Food Chemistry Department, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E-32004 Ourense, Spain.
M
M
Figueiredo-González
Nutrition and Bromatology Group, Analytical and Food Chemistry Department, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E-32004 Ourense, Spain.
B
B
Cancho-Grande
Nutrition and Bromatology Group, Analytical and Food Chemistry Department, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E-32004 Ourense, Spain. Electronic address: jsimal@uvigo.es.
J
J
Simal-Gándara
Centro de Investigação em Quı́mica, Departamento de Quı́mica e Bioquı́mica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal.
N
N
Teixeira
Centro de Investigação em Quı́mica, Departamento de Quı́mica e Bioquı́mica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal.
N
N
Mateus
Centro de Investigação em Quı́mica, Departamento de Quı́mica e Bioquı́mica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal.
V
V
De Freitas
D000872:Anthocyanins / Q000032:analysis; D003116:Color; D005511:Food Handling / Q000295:instrumentation*; D061353:Food Storage; D010636:Phenols / Q000737:chemistry*; D029963:Quercus / Q000737:chemistry*; D013053:Spectrophotometry; D013997:Time Factors; D027843:Vitis / Q000737:chemistry*; D014920:Wine / Q000032:analysis*
D000872:Anthocyanins; D010636:Phenols
Aging; Fortification with spirits; HPLC; Naturally grape dehydration process; Phenolic content; Proanthocyanidins; Sweet wines; Vitis vinifera L. cv Garnacha Tintorera