Abstract
Packaging oxygen is one of the major factors affecting beer flavour stability because residual oxygen can accelerate oxidation, aroma loss, colour change, and stale flavour formation during storage. This study evaluates the effect of packaging oxygen levels on beer flavour stability. Beer samples were packaged under controlled dissolved oxygen and total package oxygen conditions, then stored at defined temperatures for stability assessment. Dissolved oxygen, total package oxygen, aldehyde formation, colour development, bitterness retention, ester loss, sensory freshness, and stale flavour intensity were measured during storage. The results show that higher packaging oxygen levels increased oxidative markers and accelerated the development of cardboard-like and aged flavour notes. Low oxygen packaging preserved hop aroma, reduced aldehyde accumulation, and maintained better sensory freshness. Storage temperature intensified the negative effect of oxygen exposure. The study demonstrates that flavour stability depends on controlling oxygen during filling, sealing, and storage. Improved oxygen management supports longer shelf life and consistent beer quality.