[2] Allen Meadows has speculated that "based on what we know today, the most likely source of the problem is cork-related, though it appears this has been exacerbated by generally lower levels of SO2", while Steve Tanzer believes it to be a combination of several factors that involve corks, global warming resulting in overripe fruit, excessive stirring of the lees, and insufficient use of sulfur dioxide.
[5] The French oenologists Denis Dubourdieu and Valérie Lavigne-Cruege launched a theory that with the recent trends of abstaining from the use of herbicides and letting grass grow freely in the vineyards of Burgundy, the grass competing with vines for water in conjunction with a warm vintage may cause the vines to endure extreme stress.
As a result, grapes grown on highly stressed vines may have insufficient quantities of glutathione, a compound that functions as an essential antioxidant during the fermentation process.
[1] According to Michel Bettane, Burgundy producers reacted by taking steps to address the possible causes by heightened scrutiny of cork quality, more awareness of possible sulfur dioxide insufficiency, and a decrease of the practice of batonnage, the stirring of the lees that adds richness to the wines but also increases oxygen contact.
[1] In December 2006, Jamie Goode published an analysis of the problem of premature oxidation in The World of Fine Wine and explores some possible solutions.