Taint, caused by the chemical trichloroanisole, is reckoned to affect 10% of all wines. In recent years some wine producers and retailers have addressed the problem by switching to screw caps and synthetic stoppers. However, these are not universally popular. Sainsbury's says 80% of its customers prefer natural cork closures.
The retailer has recently worked with cork producer Sabate to prevent the taint occurring, culminating in the development of the new Diamond process, which uses supercritical carbon dioxide extraction to selectively remove chemical compounds, including 2,4,6 trichloroanisole, from the cork flour. The first corks treated via the process to be used on Sainsbury's products feature on its Australian Petit Verdot white.
James Gabbani, of Wimbledon-based consultant to Sabate, Cube Communications, explains: "The extraction process is a sophisticated autoclaving system via which carbon dioxide at a supercritical temperature - i.e. in a state in between gas and liquid - is used to extract the TCA, in contrast to other systems which have generally sought to kill the organism."
Fifteen months of testing by a pan-industry panel have seen around 2600 bottle samples evaluated to prove the process's efficacy. SabatŽ is already in discussions with potential wine grower customers in Australia and several UK retailers. So far Sainsbury's has been the most proactive.
