by Bob Campbell
A German company rejected 4000 cases of New Zealand wine when it found the copper levels in the wine significantly exceeded the European standard of one part per million. Copper levels in the Te Kairanga Pinot Noir
were 3.6 ppm.
Copper, in the form of copper-sulphate, is sometimes added to bulk wine to remove potentially smelly hydrogen-sulphide before the wine is bottled. The removal of excess hydrogen-sulphide is particularly important in wines sealed with a screwcap as these are more likely to develop off-odours than wines sealed with a cork.
The rejected order and associated publicity is a setback for New Zealand wine exporters. Over 95% of New Zealand wine is now packaged with a screwcap closure. Any suggestion that wine sealed with a screwcap may contain higher levels of copper seems likely to slow the acceptance of New Zealand wine in export markets.
