Progress in beer oxidation control

• Published in: ACS symposium series
• Main Author: Huige N.J
• Format: Journal Article
• Language: English
• Published: 1993
• Subjects: almacenamiento; aroma; bebidas; beers; beverages; biere; boisson; brassage; brewing; calidad; carbonyl compounds; cervezas; compose carbonyle; compuestos carbonilados; conditionnement; empaquetado; flaveur; flavour; malteado; mosto de cerveza; mout de biere; oxidacion; oxidation; oxydation; packaging; qualite; quality; stockage; storage; temperatura; temperature; wort
• ISSN: 0097-6156; 1947-5918

Beer flavor instability is caused by the formation of volatile, long chain, unsaturated carbonyls with low flavor thresholds and unpleasant flavors. Long chain unsaturated aldehydes, such as trans-2-nonenal which contributes a cardboard-like flavor, are prime contributors. Five main mechanisms for the formation of volatile, long chain, unsaturated carbonyls are discussed: 1) Strecker degradation of amino acids; 2) melanoidin mediated oxidation of higher alcohols; 3) oxidative degradation of iso-alpha-acids; 4) aldol condensation of short chain aldehydes, and, 5) enzymatic or non-enzymatic oxidation of fatty acids. Various mechanisms are most likely involved including the enzymatic degradation of fatty acids during malting and mashing followed by auto-oxidation of intermediates in the brewhouse to precursors which are oxidized in the package under the influence of free radical forms of oxygen. Various methods to minimize oxidation reaction are discussed in detail. They are: 1) maintaining a high reducing potential through oxidation control in the brewhouse; 2) minimizing oxygen pickup by the product in cellar operation, during packaging, and during product storage; 3) minimizing oxygen radicals through optimal use of endogenous and exogenous antioxidants and through minimizing copper and iron pickup; and, 4) avoidance of high storage temperatures.