Oxygen in the brewing process?
In the fermentation vessel, oxygen energizes the yeast to quickly and efficiently consume the wort sugars, preventing a slow and sluggish fermentation. Most home brewers oxygenate their wort by shaking and letting the air (only 21% oxygen) in the head space absorb into solution. The oxygen deprived yeast may start fine but may fail to develop the energy needed to complete a healthy ferment. The most notable result is a sweet and heavy taste to the beer due to slow, sluggish fermentation and a high finishing gravity. Instead of the 1.008 to 1.012 final gravity possible with the Oxynater (typical of lighter beers), a final gravity greater than 1.015 is not uncommon with air only.
