Identification and responsibility of 2,4,6-tribromoanisole in musty, corked odors in wine

In this work, gas phase chromatography analysis coupled with selective selected ion monitoring (SIM) identified 2,4,6-tribromoanisole (TBA) in wines found on tasting to have significant "musty or corked" character, although they did not contain noteworthy quantities of chloroanisoles or chlorophenols, the contaminants generally reported to cause this type of defect. The perception thresholds were studied, together with contamination conditions during winemaking, storage, and bottle-aging. A "musty" off-odor was perceptible on smelling wine containing as little as 4 ng L(-)(1) TBA, and spoilage may be detected by retro-olfaction at even lower concentrations. TBA, produced by O-methylation of its direct precursor, 2,4,6-tribromophenol, generally comes from sources in the winery environment. This paper is the first to identify the sources of a large number of cases of wines polluted during storage in premises where the atmosphere was contaminated with TBA used recently to treat wood, or originating from much older structural elements of the winery, or from used wooden containers. In certain cases, although the initial source had been eliminated, residual pollution adsorbed on walls could be sufficient to make a building unsuitable for storing wooden barrels and plastics, as well as corks, which have been found to be particularly susceptible to contamination by the TBA in the winery atmosphere.