Plastic fails wine test

A recent study in Bordeaux has shown that white wine stored in certain plastic containers oxidises inside six months.

The Institute of Vine and Wine Sciences in Bordeaux (ISVV), Europe’s largest wine research establishment, carried out the research, which was the first study of its kind into the effect of packaging on wine.

Rémy Ghidossi, lecturer at the ISVV, said: “A lot of contradictory information has been circulating in recent months regarding different packaging solutions suitable for wines.

“It is now necessary to establish the truth, based on scientific information and quantitative data, to determine the legitimacy of each package, as its main function is to preserve the flavour and characteristics of its content.”

Red and white Bordeaux wines were packaged in glass, mono PET and multi PET in 75 centilitre and 18.7cl formats and three-litre bag-in-a-box (BIB), for 12 months.

Over the study period levels of oxygen, carbon dioxide and sulphur dioxide contained in the wine as well as its taste and colour intensity were measured at regular intervals.

In conclusion, the findings showed that after six months the white wine was already showing the effects of oxidisation – and corresponding decrease in carbon dioxide levels – in the single and multi layered PET bottles and BIB. The 18.7cl single layered PET bottle proved to be the worst offender.

By contrast the wine remained stable in the two glass bottles. The chemical analyses were carried out by both expert and novice tasters and their conclusions were unanimous.

The plastic containers were also the poorest performers at retaining levels of sulphur dioxide, essential for its antiseptic and antioxidant properties, in both red and white wines.

Tasting results for the red wine were starting to emerge but it was impossible to draw any definite conclusions and tests will continue into a second year.

Rupert Millar, 13.05.2010