Do I need to aerate the wort ?
Yeast requires oxygen for healthy reproduction. At other times introducing oxygen should be avoided, as it promotes staling of the beer, but just prior to the beginning of fermentation the yeast consumes oxygen. Insufficient oxygen levels can lead to poor yeast health and poor fermentation. Aerating the cooled wort can be accomplished by straining it, using a sanitized wire whisk or motorized paint stirrer, pouring the wort back and forth at least several times between sanitized buckets from a height of several feet, or using an airstone with either an aquarium pump (a filter is recommended for the air) or pure oxygen from a welding or medical cylinder. Aeration is less important with dry yeast and when brewing lower gravity beers.
