Book with abstracts from the COST Action 0905 meeting in ... - UMB

THE PRESENCE OF COPPER (Cu 2+ ) IN WINE FROM SUB-
MEDITERRANEAN SLOVENIA
Tjaša Jug 1 , Denis Rusjan 2
1 Chamber of Agriculture and Forestry of Slovenia, Nova Gorica Institute for Agriculture
and Forestry, Pri hrastu 18, 5000 Nova Gorica, Slovenia
2 University of Ljubljana, Biotechnical Faculty, Group for viticulture, Jamnikarjeva 101,
1000 Ljubljana, Slovenia
Keywords: copper, grape, heavy metal, wine
Objectives: Copper (Cu 2+ ), as a heavy metal in grape and wine, represents a health hazard
being in strong contradiction with the growing demands for food from environmentallysound
cultivation in the EU today. The Cu content in wines has already been legally
limited to 1 mg L -1 , however excesses in its content have been observed lately, although
their proveniences mostly remain unexplained.
Methods: The 22 wine samples produced in the sub-Mediterranean winegrowing region of
Slovenia were sampled randomly in the years 2010 and 2011. In 2011 additional emphasis
was put on young wines, where the highest and excessive Cu contents were expected. The
wines’ copper content was determined with atomic absorption spectrometry (AAS).
Results: Surprisingly at all studied wines the Cu content was below legal limitation (< 1.0
mg L -1 ), furthermore 75% of the samples were below detection limit for copper (0.1 mg L -
1 ). On the other hand, young wines tended to contain higher Cu concentrations in
comparison to ageing wines, means between 0.2 and 0.3 mg L -1 .
Conclusion: The excessive Cu content in wines can be explained by its potential
provenience, from grapes’ intake of spraying or by the inappropriate use of oenological
agents. Further studies should additionally focus on the Cu provenience in wines, as human
health has to be the uppermost in the minds of all involved in wine production.