Chapter 10 - What is Different for Brewing Lager Beer?
10.1 Additional Time
The lower fermentation temperature decreases the rate at which the yeast work and lengthens both the primary and secondary fermentation times. The primary phase for ales is often 2 - 5 days, but 1 - 3 weeks is normal for a lager. As mentioned in the previous chapter, the primary and conditioning phases of fermentation happen concurrently, but the conditioning phase takes longer. This is especially true with lager yeasts. The defining character of a lager beer is a clean, crisp taste without ale fruitiness. Obviously those rotten egg odors don't belong either. The time that it takes for these compounds to be processed by the yeast can be several weeks to a few months. It depends on the malts used, the yeast strain, and the temperature at which conditioning occurs.