Musty taint

Curtis R.F., Dennis C., Gee D.G., Gee M.G., Griffiths N.M., Land D.G., Peel J.L. and Robinson D. (1974) Chloroanisoles as a cause of musty taint in chickens and their microbiological formation from chloro-anisoles in broiler house litter. J. Sci. Food. Agric., 25, 811-828. 

Robertson, R.F., Hammond, A., Jauncey, K., Beveridge, M.C.M. and Lawton, L.A. An investigation into the occurrence of geosmin responsible for earthy-musty taints in UK farmed rainbow trout, Onchorhynchus mykiss. Aquaculture, 259, 153, 2006. 

C. Dennis, and J. M. Gee 2,3,4,6-Tetrachloroanisole Association with Musty Taint in Chickens and Microbiological Formation. Nature 235, 223 (1972). 

Musty taints and off-flavors in foodstuffs have been a source of concern in the food industry for many years. Although a list of potential compounds causing this defect is long [1], the main ones responsible for it are 2-methoxy-3-isopropylpyrazine (IPMP), 2-methoxy-3-isobutylpyrazine (IBMP), 2,4,6-trichloroanisole (TCA), 2-methylisoborneol (MIB), and geosmin (GEO) (Fig. 1). 

Chloroanisoles are associated with musty taints and were detected as responsible compounds in outbreaks of this taint in chickens [3], in Rio off-... 

RF Curtis, DG Land, NM Griffiths, MG Gree, D Robinson, JL Peel, JM Gee. 2,3,4,6-Tetrachloroanisole association with musty taint in chickens and microbial formation. Nature 235 223-224, 1972. 

Nothing but the pure must is introduced into the cask—not a particle of the mash. If, in the fermenting in the vat, the scum, crest, or head, called the dhapeau by the French, be tainted with sourness or mustiness, It must be at once removed and when the fermentation of the mash does not take place with the must, the latter may be at once introduced into tbe cask. 

Pungent, musty odors Rio, medicinal, phenolic, or iodine-like flavor Musty cork flavor Iodoform taint Oxidized oil, waxy, rubbery... 

Cork taint is a musty/moldy off-odor in wine. It is related to the cork stopper, a wine botde closure made from the bark of the cork oak (Quercus suher). In a correlation between sensory evaluation and chemical analysis, 2,4,6-trichloroanisole (TCA) has b n identified as a major impact component. In sensitivity tests of a group of trained wine judges, a geometric mean of the minimum detectable concentrations of TCA has been determined at 4.6 ng/L. 

Although over 100 volatiles from finished corks have been reported (2-3), the one component that has been identified 4) as the major cause for cork taint is 2,4,6-trichloroanisole (TCA). In a recent study of Australian wines (5), 100% of the tainted wines, assessed by wine industry personnel, had TCA at or above the sensory threshold. The European QUERCUS study found TCA to be responsible for a musty/moldy taint in at least 80% of cases when it was detected in bottled wines. This makes TCA the most significant impact compound in regard to cork taint, and consequently made it the focus of our analytical developments. 

As mentioned earlier, even without being clearly identified as a musty/moldy off-character by the consumer, low levels of cork taint may be perceived as a generd loss of a wine s fruitiness, masking its aroma. 

This compound is responsible for a fungal must taint reported in the wine cork industry. Characterized by unpleasant, musty, moldy odor, and a sensory threshold in white wine of 2.1 ng/L, this compound has been assessed as the second cause of cork taint (Simpson et al., 2004). Bacteria capable of producing 2-methoxy-3,5-dimethylpyrazine could be present in areas where the cork is processed or stored. 

Some of the odor descriptions noted by the same authors are dusty, musty, earthy, wine cork taint, iodine, phenolic. 

Besides trichloroanisole, other metabolites such as guaiacol, geosmin, 2-methylisoborneol, and 2-methoxy-3,5-dimethylpyrazine (Fig. 4.4) can also cause musty or moldy aromas (Silva Pereira et al., 2000 Simpson et al., 2004). Moreover, Silva Pereira et al. (2000) pointed out that cork taints can originate from other microorganisms. As an example, a putrid odor is produced by Armillaria mellea, a microorganism that infects oak trees and causes yellow spot on corks. 

Chloroanisoles and chlorophenols are responsible for musty and medicinal taints, respectively, in foods. If one searches the literature, the majority of reported cases of contamination with these chemicals are in Europe, Australia, and Japan there are... 

FIGURE 7.2 Geosmin (tra/w-l,10-dimethyl-franj-9-decalol1 (left) and 2-methylisoborneol (right), causes of musty, earthy taints in water. 

Organic compounds sought include naturally derived materials, such as mycotoxins and off-flavours (produced by rancidification or spoilage), and man-made/industrial chemicals, e.g. pesticides, veterinary drugs, environmental contaminants (such as polychlorodibenzo-p-dioxins, polychlorinated biphenyls, polynuclear aromatic hydrocarbons, etc.) and food tainting compounds (e.g. 2,4,6-trichloro-anisole, the compound responsible for musty cork taint in wine, arising from the inappropriate use of wood preservatives). GC-MS and HPLC-API-MS are widely used for these types of analyses. Desirable food components present at trace levels, such as nutrients, are also determined using these techniques. 

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