The impact of sulphur dioxide and oxygen on the behaviour of 2‐furaldehyde in beer: an industrial approach

Summary 2‐Furaldehyde is often used as an analytical indicator of beer flavour deterioration. Although 2‐furaldehyde itself has a flavour threshold far above levels generally present in beer, it can be used as a good marker of heat damage of beer. A reversed‐phase liquid chromatographic assay, using ultraviolet‐visible detection, was applied to investigate the behaviour of 2‐furaldehyde throughout the brewing process and during extended storage of beer. The impact of storage temperature, sulphur dioxide and oxygen content on the level of 2‐furaldehyde was studied. It was found that the concentration of 2‐furaldehyde markedly increases during wort boiling and is rapidly reduced by yeast during the first hours of fermentation, emphasising the yeast reducing capacity as a determinant factor for the 2‐furaldehyde content found in the final beer. The results obtained suggest that sulphur dioxide and oxygen content play a key role on the 2‐furaldehyde content in packaged beer. 2‐Furaldehyde increase during ageing is oxygen dependent and sulphur dioxide retards its development by possibly protecting beer against the occurrence of oxidative reactions.