Premature Oxidation: a.k.a. PremOx or POX for short.
Oxidation is a coveted component to many delicately aged wines. Wines that were once bright yellow with aromas of green apple become golden, almost brown in color; and their aromas turn to those of toasted bread, cereal grains and an essence of sherry. In the case of the affected white Burgundies, the effects have materialized way too soon. Many wines that have previously been cellared for a decade or more before showing these oxidative qualities, are now showing signs within just a few short years after being bottled.
The inconsistency and mystery behind the process has lead to many perplexities and theories. Some blame the use of natural corks, while others the under usage of SO2--some have even blamed the vintage. Though a combination of these explanations may be key to understanding, none have yet to be proven true.
It all began in fall of 2003, just as the whites from the 1996 vintage were reaching seven years of age. A number of producers noticed that many of their wines were showing signs of Premature Oxidation. The same had occurred in 2002 with the 1995 vintage, but it was the first sign of it then so most chalked it off to a fluke vintage. It wasn't until it re-occurred in 2003 that buzz began about PremOx. Wines that once were cellared for a decade or more were showing partial to full oxidation by the seventh year or earlier.
The PremOx epidemic has affected every vintage from 1995 to 2004, nearly a decade without answers. The numbers have grown smaller in wines affected, but not small enough for wine makers to feel comfortable about their loss. From 1995 to 1999 the percentages of affected wines ranged from 18 to 23 %, from 2000 to 2004 it ranged from 9 to 15 %. The percentage was less, but still much higher than any one would like.
When the issue of PremOx was first raised, many Burgundy producers denied that it was happening, or at least that it affected their wines. Now, close to a decade later, it is a different story. The undeniable truth is out, and there is a mad scramble to try and solve the problem……the case of the elusive Burgundy POX!