What if the yeast is not working in brewing beer?
There are several reasons this could happen:
# The yeast was dead to begin with. # Something is wrong with
the conditions for the yeast (temperature, infection, pollution). #
The yeast was under pitched and is growing so slowly you can't
tell. The solution to numbers 1 and 3 is to re-pitch the yeast as
soon as it's apparent that the yeast is not growing. You'll want to
use a starter if possible to give the yeast a good head start over
any potential infection in the brew.
The solution to number 2 is to correct any environmental
problems (like temperature) and re-pitch the yeast as needed. If
the problem is infection or pollution, however, the batch of beer
is basically done for. You may not find this out until the
re-pitched yeast also fails to grow.
Yeast storage problems are usually the cause of number 1. Be
sure to keep liquid yeast packets refrigerated until hours before
they are ready to be used.