Transition metals in brewing and their role in wort and beer oxidative stability: a review

Beer inevitably changes over time: the colour will darken, haze may form, and stale flavours develop, while others fade. The challenge of maintaining fresh flavour quality beer (over a typical 9-12 month storage period) is generally determining factor beer's shelf-life for brewers, as opposed to colloidal or microbiological stability. Fortunately, early brewhouse, oxidative degradation can - certain extent be controlled, enabling increased. This review considers general issues stability, mechanisms ageing, ways quantifying staleness staling potential, current practical approaches prevent ageing. Emphasis placed on catalytic role iron, copper manganese oxidation during brewing storage; how removal and/or inhibition these prooxidative transition metal ions leads prolonged (flavour)