A measurement of the density of fermentable sugars in a mixture of malt and water with which a brewer begins a given batch. Abbreviated O.G. Strictly speaking, the specific gravity, but usually "gravity" to mean the degree Balling or Plato of the wort leaving the brew kettle.

Respiratory enzymes which catalyze oxidation changes.

In a narrow sense, oxidation means the chemical addition of oxygen to a substance.

Stale flavor of wet cardboard, paper, rotten pineapple, or sherry, as a result of oxygen as the beer ages or is exposed to high temperatures.