packaging
Packaging
Move finished beer into its final container with as little oxygen pickup as possible, because oxygen taken up here determines how the beer ages.
What is actually happening
Lines and containers are purged with CO₂ and filled under counter-pressure so the beer never falls through air. Cans are typically dosed with a drop of water or CO₂ immediately before seaming to displace the headspace.
Total packaged oxygen is one of the most closely watched numbers in a modern brewery, because everything about how the beer will taste in three months follows from it.
What goes wrong here
Risks rather than certainties. This step does not cause these faults; getting it wrong can.
- Oxidation — The universal ageing fault: oxygen degrades beer into papery, cardboard-like staleness, and dulls everything that made it good.
- Infection — Unintended microbial growth — which is a fault only because it was unintended, since the same organisms define lambic.
- Lightstrike — Light breaks down hop compounds into a thiol chemically close to skunk spray — the fastest fault in beer, and entirely preventable.
Related steps and concepts
- Force carbonation — What usually precedes it.
- Pasteurisation — What may follow it.
Also at the packaging stage
Cask breather · Pasteurisation
See the whole process in order on how beer is made.
Last reviewed 2026-08-16.
Evidence
What BeerHQ knows about this, and how. Every statement carries the state of the evidence behind it rather than being presented flatly as fact.
William Painter’s crown cork, patented in 1892, gave bottled beer a cheap and reliable seal and is the reason beer bottles need no cork and should be stored upright rather than laid down.
Backed by a source
Source: Beer: The Story of the Pint — print
Total packaged oxygen — the oxygen picked up at filling rather than admitted afterwards — is the dominant determinant of how a beer will taste after months in the package.
Backed by a source
Sources: Technology Brewing and Malting — print; Institute of Brewing & Distilling technical publications