Terroir 2004 banner
IVES 9 IVES Conference Series 9 TCA – A status report on South African cork closures

TCA – A status report on South African cork closures

Abstract

Cork taint decreases the commercial value of wine as tainted wines are rejected by consumers. Although other compounds in wine and cork can also be responsible for causing a taint, 2,4,6-trichloroanisole (TCA) is regarded as the primary cause of cork taint. As cork taint is often used in marketing campaigns against natural cork closures, manufacturers extended their overall quality control to monitoring TCA levels. Since August 2004 a representative sample of all batches of cork closures that are imported by members of the South African Cork Quality Council (SACQC) are tested for TCA before release into the market. Quality control on TCA is conducted by an independent laboratory, established by the Institute for Wine Biotechnology (Department of Viticulture and Oenology, University of Stellenbosch) and Thalès Wine Cellar Services (Pty) Ltd. In this contribution we report on the current status of TCA in cork closures in South Africa. The analytical methodologies as well as the quality control program that is currently implemented are also outlined.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article

Authors

J.A. Minnaar

Institute for Wine Biotechnology, University of Stellenbosch, Private Bag X1, Stellenbosch, 7600, South Africa

Contact the author

Tags

IVES Conference Series | Terroir 2004

Citation

Related articles…

Impact of changes in pruning practices on vine growth and yield

A gradual decline in vineyards has been observed over the past twenty years worldwide. This might be explained by the climate change, practices change or the increase of dieback diseases. To increase the longevity of vines, we studied the impact of different pruning strategies in four adult and four young vineyards located in France and Spain. In France, vineyards were planted with Cabernet franc on 3309C while Spanish trials were planted with Tempranillo grafted on 110R. Vegetative expression, yield, quality of berries and wood vessels conductivity were measured. The distribution of vegetative expression, yield and berry composition between primary and secondary vegetation were quantified. Finally, tomography was used to evaluate the implication of the treatments on sap flows.
First results show that i) the respectful pruning leads to an increase of 30 to 50% more secondary shoots than the aggressive pruning in France and between 15 and 20% in Spain, ii) there is no major effect on the yield over the first two years following the implementation of the new pruning practices, although the proportion of clusters from suckers is higher on the respectful pruning method. On young vines, the development of the trunk according to a respectful pruning leads to a loss of harvest 2 years after planting. This is due to the removal, on the future trunk, of the green suckers which carrying bunches. This operation carried out in spring rather than during winter pruning, would promote a better leaf / fruit balance when the plant comes into production, and could lead to better hydraulic conduction in the vessels of the trunk. Maintaining these trials for several years will provide more robust data to assess the impact of these practices on the vines over the long term.

Agroclimatic characterization of Monreale DOC appellation for vine growing

This paper presents the results of an agroclimatic study of the viticulture area called DOC Monreale (Pa), Italy, which was carried out with the aim to supply a working instrument supporting viticulture planning.

Using unmanned aerial vehicle with multispectral camara to efficiently and precisely monitor the incidence of downy mildew and technical maturity of beibinghong (vitis amurensis Rpru.) grapes 

Multispectral unmanned aerial vehicle (UAV) has been successfully applied in monitoring vine vegetative growth, however, there are still potential relationships between remote sensing vegetation indexes (vis) and vine condition or grape quality, so it is worthy a deeper investigation to make a better use of UAV. One of the purposes of the study is to find out vis that could denote the severity of downy mildew (DM), so that precise and differentiated control strategies would be adopted subsequently.

Emerging pest pressures in viticulture: a brief review of Argyrotaenia Ljungiana in Eastern Europe

As viticulture faces increasing threats from emerging pests, understanding and dealing with new infestations is crucial.

Effect of rising atmospheric CO2 levels on grapevine yield and composition by the middle of the 21st century: what can we learn from the VineyardFACE?

Atmospheric CO2 levels have been rising continuously since the industrial revolution, affecting crop physiology, yield and quality of harvest products, and grapevine is no exception [1]. Most of previously reported studies used potted plants in controlled environments, and explored grapevine response to relatively high CO2 levels, 700 ppm or more. The vineyardFACE, established in Geisenheim in 2012, uses a free air carbon dioxide enrichment (FACE) system to simulate a moderate (ambient +20%) increase in atmospheric CO2 in a vineyard planted with cvs. Cabernet-Sauvignon and Riesling grafted on rootstock 161-49 Couderc and SO4, respectively.