The Art of Culturing
Yeast
Master Terafan Greydragon
University of Atlantia
1 February A.S. XXI
Why culture yeast
• Every time you brew mead,
beer, or wine you MUST
HAVE a yeast culture
• Liquid cultures are VASTLY
superior to dry yeast, especially
in terms of consistency, flavour,
and use
• If you use a “fresh” liquid
culture every time, it can
become cost prohibitive ($4-6
per batch)
• You can achieve “personalized”
yeast (stable mutations) with
unique consistency
Ways to Culture Yeast
• Create pure agar slants
• Brew enough to pitch from
batch to batch
• Home culture generation to
generation until you have a
stable mutation
Pure Agar Slants
•
•
•
•
Create sterile agar solutions
Innoculate with fresh liquid culture
Release pressure every 2 days
After a week, you should have a
PURE WHITE film
• Slants should stay active 4-6 months
Pitching batch to batch
• Brew your first batch and pitch
the yeast
• ***
• Within 2 weeks (5-8 days is ideal)
draw off a quart of the rapidly
fermenting liquid
• Keep in the refrigerator less than 7
days
• Brew another batch and add the
quart you drew off (after letting it
warm to room temp)
• Repeat from ***
Home Culture
• Brew your first batch and pitch the yeast,
keeping 1 quart of must separate (freshly
boiled) (This is the ‘sterile must’)
• ***
• Between 5-8 days draw off 1 quart, in two
quart jar, and place in refrigerator
• Every 14 days, let jar and sterile must
warm to room temperature, and add 1/2
cup of the sterile must to jar
• Let sit 4 hours and return to refrigerator
• Brew another batch and add that 1-2 quarts
(after letting it warm to room temp)
• Repeat from ***
Adding a 1/2 cup of sterile must every 14 days will provide enough fermentable
sugars on a regular controlled basis to extend the life of your yeast for years.
Very similar in method to keeping a "sourdough starter" alive, you must feed
your yeast every two weeks. The low temperature in the refrigerator keeps the
yeast working very slowly, but still alive.
Alternate Sterile Musts
Each of these below is a 'sterile' must that can be used to maintain the
steady growth and life of your yeast culture
• 1 TBS malt, 1/16 tsp yeast nutrient,
1 cup water
• 1/4 cup malt, 1/4 tsp yeast nutrient, 1
quart water
• 1 cup malt, 1 tsp yeast nutrient, 1
gallon water
• 1 /4 cup dextrose, 1/4 tsp yeast
nutrient, 1 quart water
• 1/2 cup honey, 1/2 tsp yeast nutrient,
1 quart water
• 1/4 cup sugar, 1/4 tsp yeast nutrient,
2 cups water, 2 cups pasteurized
juice (boiled)
Bibliography
• Leistad, Rog, Yeast culturing for the
Homebrewer, GW Kent Inc, Ann
Arbor, MI, Dec 1983
• Crenshaw, Donald G. “Yeast cycles
and Fermentation”, Zymurgy,
American Homebrewers Assocation,
Boulder, CO, Fall 1983
• Eckhardt, Fred, The Amateur
Brewer, J.I. Takita, Portland, OR,
Summer 1979