Subtlety is the defining characteristic of lagers. Compared to the more in-your-face personality of ales, lagers are suave and reserved. If ales are frisky puppies, lagers are purring cats. They’re not climbing up your legs; you have to meet them where they are. But lagers offer easy drinkability, a transparent showcase for brewing ingredients and sublime delights—beer after beer.
And it’s the unique characteristics of their yeast that set them apart.
Crazy Mixed-Up Yeast
Lager yeast, Saccharomyces pastorianus, is designated as a species apart from S. cerevesiae, or ale yeast. S. pastorianus is a cold-tolerant hybrid between ale yeast and a recently identified cold-tolerant species called S. bayanus—which is itself a hybrid that includes DNA from another cold-tolerant yeast, S. uvarum, with some from S. cerevisiae.