Whisky metal

The chief advantage of wood for containers is that many common species are free from harmful contaminants. For this reason wood had widespread use in the food and beverage industries, but it has now suffered severe competition from corrosion-resistant metals, plastics and paper products. Oak had a very extensive use in tight cooperage in the brewing industry, and its use for barrels still survives in the maturing of whisky and brandy and in the wine industries. Wood is particularly useful where acetic acid is present as this acid is corrosive to most common metals. 

Adam, T., Duthie, E., Feldmann, J. Investigations into the use of copper and other metals as indicators for the authenticity of Scotch whiskies. J. Inst. Brew. 108, 459 64 (2002)... 

Tequila, whisky, vodka and red wine [55] Discrimination between the four types of beverages 18 metal oxide sensors... 

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