Do you need to save a couple dollars but NEED to brew? Try washing your yeast! It's a simple way to reuse viable yeast and save money. You'll do this washing immediately after transferring your beer off of the primary yeast cake.
Boil one gallon of water for 15 minutes, while your waiting sanitize one large container (like a 1 gallon jug), a few large mason jars and lids and a funnel. Ideally, you'd boil the jars and lids, too.
When your timer is up, chill the kettle of water in an ice bath (like you would wort).
Siphon your beer off the yeast into a secondary fermentor, bottles or a keg. Sanitize and return the airlock to the fermentor.
After your water has chilled, make sure it is at room temperature and pour it into the primary fermentor (that contains the yeast cake). Shake it up!
Place carboy on its side and let it settle for 30 minutes. There should be definable layers. The yeast is the milky layer.
Carefully pour that milky, yeast layer into the sanitized 1 gallon jug , leaving as much of the dead yeast and hop particles behind as possible. Place an airlock on this container, and let settle for another 30 minutes.
After it has settled, pour into sanitized jars, seal them up and place in refrigerator.
Use within 3 months or so -- as always with yeast, the fresher, the better!
