When The Microbes Are Happy, The Brewer Is Happy Yeast can be
pretty demanding little buggers, despite being unicellular
microscopic organisms. Brewers know they must appease them to
get the beer they want. "It's yeast-strain dependent, it's
environment, it's temperature, oxygen levels," says Matt Brophy,
brewmaster of Flying Dog Brewery in Frederick, Md. "There's a
lot of variables that you need to have a high level of control
over." Yeast produces hundreds of chemical compounds that can
affect the beer's ultimate flavor, appearance and stability.
Over the centuries, humans have domesticated yeast strains with
the best characteristics for brewing, so that the ones brewers
use today are much more effective than wild yeast. It's kind of
like going with a pedigreed Best In Show at Westminster, rather
than a coyote. "We deal with cultured yeast — very specific
strains that give us flavor profiles that we desire in our
beers," Brophy says. Then they have to pamper the yeast with the
right conditions. It gets fed