Worty flavours

Perpete P. and Collin S. How to improve the enzymatic worty flavour reduction in a cold contact fermentation. Food Chemistry 70 (4) (2000) 457-462. 

Perpete, R, Collin, S. (1999). Fate of the worty flavours in a cold contact fermentation. Food Chemistry, 66, 359-363. 

Methional is also the key compound responsible for the defect of alcohol-free beers described as worty flavour. The other off-flavour in milk is a cardboard-like or metallic flavour, which develops in milk with a prolonged exposure to light. Compounds responsible for this off-flavour are secondary lipid oxidation products, such as hexanal, pentanal and some other substances formed by riboflavin-catalysed photooxidation of fatty acids. 

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