A bottom-fermented Vienna- or marzen-style beer, originally
brewed for Germany's Oktoberfest celebration. Copper-colored,
malty, and sweet.
Old Ale
In Britain, a medium-strong dark ale most often consumed in
winter.
Original Gravity
The density of the wort prior to fermentation, expressed as a ratio
as compared to the density of water. A measure of the amount of
solids in the wort.
Oxidation
When a packaged beer is stored for a period of time, it stales, or
oxidizes. Different beers stale at different rates and develop off
flavors. The rate of oxidation goes up as the temperature goes up.
Oxidation is familiar to drinkers as a papery or cardboard like
character in both taste and aroma.