125^thAnniversary Review: The role of proteins in beer redox stability

Abstract

Flavour stability is usually approached through inhibition of reactive oxygen species (ROS). It may be possible to suppress ROS, but never to entirely eliminate them in packaged beer. The role of proteins in ROS suppression seems to have been lost in the compliant acquiescence to supply haze-free bright beer. Proteomics allows beer polypeptides to be finely resolved, identified and correlated with beer quality and stability. This has already produced a broader view of what stabilizes beer foam. No doubt it could do the same for beer stability and the broader roles that proteins, such as LTP1, can have in redox reactions and free radical suppression. Cysteine oxidation and reversibility is central to cellular signalling in biological systems. Thiol chemistry is also integral to beer redox stability. We can, and should, extrapolate the recent biological findings to the simple pleasure of creating a high-quality beer.

Drought-proofing barley (Hordeum vulgare) and its impact on grain quality: A review

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Impact of yeast and bacteria on beer appearance and flavour

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