Guinness stout and Bud Lite differ in, to be conservative, several ways, but one is that they’re brewed with very different types of yeast. Lager isn’t just a beer style, it’s a yeast lifestyle. Humans have been brewing with ale yeast—Saccharomyces cerevisiae—for thousands of years. But it was less than 600 years ago that European brewers stumbled on lager yeast, which behaves very differently and produces that distinctive lager flavor.
Office of Strategic Communication