Every once in awhile I plan to review a scientific journal article which I’ve found particularly interesting or noteworthy. I’ve got quite a few to choose from, so there’s no lack of material.
One of the most informative articles I’ve seen is from Food Chemistry 95, 2006, titled “The chemistry of beer aging – a critical review”, by Vanderhaegen, et al. This beast of a paper is 24 pages long, with 5 pages of references (roughly 220 of them). It covers a vast amount of the research that has been put towards the processes behind beer aging, mostly focusing on the evolution of staling and oxidation flavors. Here’s the abstract:
Currently, the main quality problem of beer is the change of its chemical composition during storage, which alters the sensory properties. A variety of flavours may arise, depending on the beer type and the storage conditions. In contrast to some wines, beer aging is usually considered negative for flavour quality. The main focus of research on beer aging has been the study of the cardboard-flavoured component (E)-2-nonenal and its formation by lipid oxidation. Other stale flavours are less described, but may be at least as important for the overall sensory impression of aged beer. Their origin has been increasingly investigated in recent years. This review summarizes current knowledge about the chemical origin of various aging flavours, and the reaction mechanisms responsible for their formation. Furthermore, the relationship between the production process and beer flavour stability is described.
This article kicks off with an interesting (and at times frustrating) observation of beer drinkers: “de gustibus et coloribus non est distputandum” – or “there’s no accounting for taste”. I’ve seen this more times than I can count, where oxidized flavors are either not noticed or, even worse, expected to be there as part of the intended flavor of the beer. I suppose you’d have to admit that, by now, the lightstruck flavor of Corona and
Rolling Rock [ed: apparently Rolling Rock is no longer skunky due to use of reduced hop extracts] would now be considered a ubiquitous and expected flavor of those beers. Do people who drink Corona out of a bottle like the flavor of Corona from a can? I certainly like the canned version better. The Paper, henceforth to be referred as such, even points to a study by the always entertaining Charlie Bamforth which demonstrated that aging flavors are not always regarded as off-flavors. What dictated acceptance of the beer was whether they recognized the flavor of the brand, only so much as it remains consistant.