Project Number
WW WDT 10-03
Project title
Methods to improve Sauvignon blanc wine quality and diversity in South Africa
Project leader
Du Toit, W J
Institution
University of Stellenbosch. Department of AgriSciences. Department of Viticulture and Oenology
Team members
Du Toit, W J
Coetzee, C
Kritzinger, E
Deloire, A
Project description
The main aim of this project is to assess the influence of various production techniques on Sauvignon blanc grapes, wine composition and quality. These would include different oxygen and sulphur dioxide additions during different stages of winemaking. Different oxygen and sulphur dioxide additions to juice and its effect on various flavour, phenolics and glutathione were thus investigated. It was found that oxygen additions led to lower glutathione, caftaric acid and thiol levels, but this process was negated by the addition of sufficient sulphur dioxide. Sulphur dioxide and oxygen additions also seem to affect other volatile compounds such as esters, higher alcohols etc. Preliminary results indicate that the yeast strain could also play a role in glutathione levels in Sauvignon blanc wines
Poster(s)
Coetzee, C, Lisjak, K, Nicolau, L and Du Toit, W J. 2010. Different oxygen and sulphur dioxide concentrations in Sauvignon blanc must: Effect on the composition of the must and wine. Poster presented at the 4th International Congress of the South African Society for Enology and Viticulture. 28-30 July, Cape Town, South Africa.
Presentation(s)
Fracassetti, D and Du Toit, W J. 2010. Oxygen consumption in Sauvignon blanc wines: Role played by glutathione, sulphur dioxide and phenolic compounds. Paper presented at the 4th International Congress of the South African Society for Enology and Viticulture. 28-30 July, Cape Town, South Africa.
Fracassetti, D, Lawrence, N, Tredoux, A G J, Tirelli, A, Nieuwoudt, H H and Du Toit, W J. 2010. Quantification of glutathione in must and wine by ultra-performance liquid chromatography. Paper presented at the 4th International Congress of the South African Society for Enology and Viticulture. 28-30 July, Cape Town, South Africa.
Kritzinger, E C, Bauer, F F and Du Toit, W J. 2010. Influence of yeast strain and extended lees contact on glutathione levels in Sauvignon blanc wine. Paper presented at the 4th International Congress of the South African Society for Enology and Viticulture. 28-30 July. Cape Town, South Africa.
Du Toit, W J, Coetzee, C, Kritzinger, E and Fracassetti, D. 2012. Glutathione: Recent developments on our knowledge on this important anti-oxidant. Paper presented at the 34th National Congress of the South African Society for Enology and Viticulture. 14-16 November, Somerset West, South Africa.
Article
Fracassetti, D, Lawrence, N, Tredoux, A G J, Tirelli, A, Nieuwoudt, H H, Du Toit, W J. 2011. Quantification of glutathione, catechin and caffeic acid in grape juice and wine by a novel ultra-performance liquid chromatography method, Food Chemistry, v. 128 (p. 1136-1142)
Coetzee, C, Du Toit, W J. 2012. A comprehensive review on Sauvignon blanc aroma with a focus on certain positive volatile thiols, Food Research International, v. 45 (1) (p. 287-298)
10.1016/j.foodres.2011.09.017
Coetzee, C, Lisjak, K, Nicolau, L, Kilmartin, P A, Du Toit, W J. 2013. Oxygen and sulphur dioxide additions to Sauvignon blanc: Effect on must and wine composition, Flavour and Fragrance Journal, v. 28 (3) (p. 155-167)
Du Toit, W J, Kritzinger, E C. 2013. Glutatioon in wyn: Nuwe belangstelling, WineLand, Mnth Sep (p. 98-99)
Article.pdf
Fracassetti, D, Coetzee, C, Vanzo, A, Ballabio, D, Du Toit, W J. 2013. Oxygen consumption in South African Sauvignon blanc wines: Role of glutathione, sulphur dioxide and certain phenolics, South African Journal of Enology and Viticulture, v. 34 (2) (p. 156-169)
Article.pdf
Kritzinger, E C, Bauer, F F, Du Toit, W J. 2013. Influence of yeast strain, extended lees contact and nitrogen supplementation on glutathione concentration in wine, Australian Journal of Grape and Wine Research, Mnth Jun v. 19 (2) (p. 161-170)
Article.pdf
Kritzinger, E C, Stander, M A, Du Toi, W J. 2013. Assessment of glutathione levels in model solution and grape ferments supplemented with glutathione-enriched inactive dry yeast preparations using a novel UPLC-MS/MS method, Food Additives and Contaminants. Part A. Chemistry, Analysis, Control, Exposure and Risk Assessment, v. 30 (1) (p. 80-92)
10.1080/19440049.2012.728723
Kritzinger, E C, Bauer, F F, Du Toit, W J. 2013. Role of glutathione in winemaking: a review. Journal of Agricultural and Food Chemistry, Mnth Jan v. 61 (2) (p. 269-277)
10.1021/jf303665z
Van Wyngaard, E, Brand, J, Jacobson, D. 2014. Sensory interaction between 3-mercaptohexan-1-ol and 2-isobutyl-3-methoxypyrazine in dearomatised Sauvignon Blanch wine, Australian Journal of Grape and Wine Research, v. 20 (2) (p. 178-185)
Article.pdf
Paper
Du Toit, W J, Buica, C, Coetzee, C, Wyngaard, E, Moffat, T, Strever, A E. 2011. Handling grapes from a warm area: How to burn your fingers, IN: Proceedings of the 16th International Enology Symposium. 16-18 May 2011, Bozen, South Tyrol, Italy. (p. 53-56)
Du Toit, W J, Coetzee, C, Lisjak, K, Nicolau, L. 2011. Different oxygen and sulphur dioxide concentrations in Sauvignon blanc must: Effect on the composition of the must and wine, IN: 3rd International Symposium on Macromolecules and Secondary Metabolites of Grapevine and Wines: MacroWine 2010. 16-18 June 2010, Torino, Italy. (p. 217-220)
Kritzinger, E C, Bauer, F F, Du Toit, W J. 2011. Influence of yeast strain, extended lees contact and juice composition on glutathione levels in wine, IN: Chassagne, D (ed). Proceedings of the Wine Active Compounds 2011: Second Edition of the International Conference Series on Wine Active Compounds. 24-26 March 2011, Beaune, France. (p. 83-85)
Thesis
Coetzee, C. 2011. Effect of oxygen on Sauvignon blanc. MScAgric. University of Stellenbosch, Stellenbosch, South Africa.