Oxygen Absorption in Beer Bottling Modern Bottling Technology as an answer to known challenges

Brewers know: Beer is probably the drink that is most sensitive to oxygen. The so-called oxidation taste occurs when oxygen intake is too high. Trendy beers with the rediscovered dry hopping, previously called “hopping”, change their taste quite quickly when oxygen is absorbed. But ordinary light beers are also particularly sensitive to oxygen. Darker beers, on the other hand, often show a considerable taste tolerance to oxygen levels beyond 0.1 mg/l.

The oxygen absorption during beer preparation begins when the malt is crushed and does not end when the beer leaves the brewery, because oxygen penetrates, for example, seals in crown caps - until the beer is consumed. Beer ingredients react so quickly with oxygen that measurements of dissolved oxygen are necessary immediately after the respective processes such as tank filling, filtration or bottling. An oxidized beer with the typical taste changes often has barely measurable oxygen levels, and yet the loss of quality is significant.

The use of additives such as bisulfite or ascorbic acid as oxygen scavengers is common in other countries outside of Germany, especially for filling in PET bottles. Because these containers and the PE or PP closure most commonly used for them allow oxygen to migrate in relevant quantities in a short time. However, as an antioxidant for beer, ascorbic acid is a double-edged sword. Oxidation processes - not only in beer, but also in other beverages such as soft drinks or juices - are complex processes with many intermediate stages, and therefore much more than the transfer of oxygen to a specific recipient molecule. Are the polyphenols in malt or hops beneficial antioxidants or harmful clouding agents? This is a chapter in itself,

To meet this challenge, breweries are developing different approaches to quality assurance: from low-polyphenol malts to polyphenol-rich cone hops or from preservation strategies to precipitation to the reduction of polyphenols using PVPP.

Avoiding or reducing oxygen intake for flavor stability