Yeast
Preparation & Yeast
Starters
USING DRY YEAST- Most dry yeast will start the fermentation
quickly without any preparation. It is important to use fresh yeast.
To improve the chances of a good fermentation with dry yeast, the
yeast can be rehydrated in a small amount of sterile water before
adding to the beer. The water should be the same temperature as
the fermentation temperature of the beer you are making. A yeast
starter can be made with dry yeast (see below).
USING LIQUID YEAST- The most common form of liquid yeast
available to home brewers is Wyeast, which comes in a foil packet.
The packet contains instructions for popping the inner pouch to
start the yeast growth. This is usually done the day before brewing,
unless the Wyeast packet is more than a month old. For each month
beyond one month, pop the package an additional day in advance
of brewing, up to 4 days. Thus, if your packet is two months old,
pop the yeast two days before brewing; if it is six months old,
pop the yeast 4 days before brewing.
MAKING A YEAST STARTER:
This is usually done the day before you brew. A yeast starter
will start the fermentation of you beer more rapidly.
Equipment needed:
Starter vessel: quart size or larger
jar (juice jars work well), a large beer bottle, or an Erlenmeyer
flask
Stopper & Airlock*
Measuring cups, measuring spoons
Rubbing alcohol & cotton
balls or swabs
*If you do not
have a stopper that fits your chosen starter vessel, you may
cover the container with a clean cloth that has
been sanitized: boil the cloth for 10 minutes, and then soak it
in a sanitizing solution. If using cheesecloth, or other loosely
woven cloth, use 2- 4 layers so dust and bacteria are effectively
trapped.
The starter should be at least 2 cups in size. Before making the
starter, if using liquid yeast, follow the instructions above for
starting the yeast growth.
To make a starter medium, use malt extract, dried malt extract,
or some unfermented wort from a previous batch. It is important
to use malt based sugars, as other sugars do not have sufficient
nutrients for healthy yeast growth. Add water to the extract or
gyle- the best specific gravity range for making a yeast starter
is between 1.030- 1.040. Here are some guidelines for making starters
with organic malt extract:
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STARTER VOLUME
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VOLUME OF EXTRACT
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YEAST NUTRIENT (Optional)
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HOPS (optional)
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1 cup
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1 Tablespoon
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1/2 tsp.
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1/2 tsp.
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2 cups
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2 Tablespoons
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1 tsp.
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1 tsp.
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1 Quart
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1/4 cup
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1 Tablespoon
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1 Tablespoon
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(For larger volumes, adjust above quantities
equally)
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Boil the starter solution for 15- 20 minutes, allow to cool to
70 oF, and pour it into your sanitized yeast starter
vessel. Add the yeast from the pouch, or the dry yeast. Shake well
to add oxygen and cover or seal with an airlock. Add the starter
to you unfermented beer as soon as it has cooled to 70 oF Before
pouring the yeast from the starter container, swab the lip of the
container with alcohol to kill bacteria living there. If you wish,
you can save a small portion of the starter (1/4 cup is adequate)
to reactivate for a later batch. The saved starter can be stored
in the refrigerator with an airlock (a cloth cover is not recommended
for long term storage!) on it for up to 1 month. To save your yeast
for a longer period of time, make a new starter from the old one.
When pitching stored yeast into your beer, you should also make
a new starter.
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