How Long Will Your Cultures Last?

Once you’ve ordered your starters, it’s important to know how to store them, and how to store the resulting cultured foods, to get the maximum benefit from your purchase. Our cultures do have a “best by” label, but it also helps to know the general expiration period for the cultures and the products they make.

The following information indicates how long you can expect cultures to be good at room temperature, in the refrigerator, or in the freezer. These times are given as a recommendation based on our experience with the cultures. Local conditions, including temperature and hygiene, may shorten or lengthen the time that your cultures remain viable.

Yogurt Cultures

Direct-set cultures (Traditional Flavor, Mild Flavor, Vegan)

  • At room temperature (68° to 78°F): 3 to 4 weeks
  • In the refrigerator (40° to 45°F): 6 to 12 months
  • In the freezer (0° to 25°F): 12+ months
  • Maximum culturing temperature: 112°F


Heirloom Thermophilic Cultures (Greek, Bulgarian)

  • At room temperature (68° to 78°F): 3 to 4 months
  • In the refrigerator (40° to 45°F): 9 months unopened
  • In the freezer (0° to 25°F): 12 months unopened
  • Maximum culturing temperature: 112°F


Heirloom Mesophilic Cultures (Viili, Filmjölk, Matsoni, Piimä)

  • At room temperature (68° to 77°F): 3 to 4 months
  • In the refrigerator (40° to 45°F): 9 months unopened
  • In the freezer (0° to 25°F): 12 months unopened
  • Maximum culturing temperature: 77°F


Yogurt

  • At room temperature (68° to 78°F): 3 to 6 hours (may remain edible for longer)
  • In the refrigerator (40° to 45°F): 7 days to maintain re-culturing viability; 2 weeks for edibility
  • In the freezer (0° to 25°F): 2 to 3 weeks to maintain re-culturing viability; 1 to 2 months (like ice cream) for edibility
  • Storage recommendation: Refrigerate

 

Kefir Grains and Cultures

Dried Milk Kefir Grains

  • At room temperature (68° to 78°F): 12 to 18 months
  • In the refrigerator (40° to 45°F): 18+ months
  • In the freezer (0° to 25°F): not recommended
  • Maximum culturing temperature: 85°F


Milk Kefir Starter Culture

  • At room temperature (68° to 78°F): 3 to 4 weeks
  • In the refrigerator (40° to 45°F): 6 to 12 months
  • In the freezer (0° to 25°F): 12+ months
  • Maximum culturing temperature: 85°F


Milk Kefir Grains in Milk

  • At room temperature (68° to 78°F): 2 days
  • In the refrigerator (40° to 45°F): 1 to 2 weeks
  • In the freezer (0° to 25°F): not recommended
  • Maximum culturing temperature: 85°F


Milk Kefir

  • At room temperature (68° to 78°F): 1 to 2 days
  • In the refrigerator (40° to 45°F): 2 to 3 weeks
  • In the freezer (0° to 25°F): 1 to 2 months or longer (like ice cream)
  • Storage recommendation: Refrigerate


Dried Water Kefir Grains

  • At room temperature (68° to 78°F): 12 to 18 months
  • In the refrigerator (40° to 45°F): 18+ months
  • In the freezer (0° to 25°F): not recommended
  • Maximum culturing temperature: 85°F


Water Kefir Grains in Sugar Water

  • At room temperature (68° to 78°F): 3 days
  • In the refrigerator (40° to 45°F): 2 weeks or more
  • In the freezer (0° to 25°F): not recommended
  • Maximum culturing temperature: 85°F


Water Kefir

  • At room temperature (68° to 78°F): 3 to 4 days
  • In the refrigerator (40° to 45°F): 2 to 3 weeks
  • In the freezer (0° to 25°F): 1 to 2 months (like ice cream)
  • Storage recommendation: Refrigerate

 

Buttermilk and Sour Cream

Buttermilk Starter (heirloom)

  • At room temperature (68° to 78°F): 3 to 4 months
  • In the refrigerator (40° to 45°F): 9 months
  • In the freezer (0° to 25°F): 12+ months
  • Maximum culturing temperature: 80°F


Buttermilk/Sour Cream Starter (direct-set)

  • At room temperature (68° to 78°F): 3 to 4 weeks
  • In the refrigerator (40° to 45°F): 3 months
  • In the freezer (0° to 25°F): 12+ months
  • Maximum culturing temperature: 80°F


Buttermilk

  • At room temperature (68° to 78°F): 4 to 6 hours (may remain edible for longer)
  • In the refrigerator (40° to 45°F): 7 days for heirloom variety to maintain culturing viability; 2 weeks for edibility
  • In the freezer (0° to 25°F): 2 to 3 weeks to maintain re-culturing viability; 1 to 2 months (like ice cream) for edibility
  • Storage recommendation: Refrigerate


Sour Cream

  • At room temperature (68° to 78°F): 4 to 6 hours (may remain edible for longer)
  • In the refrigerator (40° to 45°F): 1 to 2 weeks
  • In the freezer (0° to 25°F): 1 to 2 months (like ice cream)
  • Storage recommendation: Refrigerate

 

Kombucha

Dried Kombucha Starter Culture (Scoby)

  • At room temperature (68° to 78°F): 3 to 4 weeks
  • In the refrigerator (40° to 45°F): 9 months
  • In the freezer (0° to 25°F): not recommended
  • Maximum culturing temperature: 85°F


Active Kombucha Starter Culture (Scoby) in sugared tea / kombucha

  • At room temperature (68° to 78°F): 45 days
  • In the refrigerator (40° to 45°F): 60 to 90 days
  • In the freezer (0° to 25°F): not recommended
  • Maximum culturing temperature: 85°F


Kombucha

  • At room temperature (68° to 78°F): up to 1 week, depending on sugar content (carbonation may build up)
  • In the refrigerator (40° to 45°F): 2 to 4 weeks
  • In the freezer (0° to 25°F): 1 to 2 months (like ice cream) (will lose its fizz)
  • Storage recommendation: Refrigerate

 

Cultured Vegetables

Caldwell’s Vegetable Starter Culture

  • At room temperature (68° to 78°F): 6 months
  • In the refrigerator (40° to 45°F): 12 months
  • In the freezer (0° to 25°F): 12 months
  • Maximum culturing temperature: 110°F


Body Ecology Starter Culture

  • At room temperature (68° to 78°F): 6 months
  • In the refrigerator (40° to 45°F): 8 months
  • In the freezer (0° to 25°F): 12 months
  • Maximum culturing temperature: 110°F

 

Cheese Cultures

Direct-set Starter Cultures

  • At room temperature (68° to 78°F): 3 to 4 weeks
  • In the refrigerator (40° to 45°F): 6 to 12 months
  • In the freezer (0° to 25°F): 12+ months
  • Maximum culturing temperature: 110°F


Cheese

  • At room temperature (68° to 78°F): A day or two, depending on the cheese
  • In the refrigerator (40° to 45°F): 2 to 3 months
  • In the freezer (0° to 25°F): Up to a year
  • Storage recommendation: Cool, dry location, or refrigerate. Soft cheeses will keep 2 to 3 weeks; hard cheeses will keep for 2 to 3 months. Depends on the cheese and how it is wrapped.

 

Sourdough

Dehydrated Sourdough Cultures

  • At room temperature (68° to 78°F): 12 months
  • In the refrigerator (40° to 45°F): 12+ months
  • In the freezer (0° to 25°F): 12+ months
  • Maximum culturing temperature: 90°F


Active Sourdough Starter (wheat and similar flours)

  • At room temperature (68° to 78°F): 8 to 12 hours between feedings; can last up to 24 hours
  • In the refrigerator (40° to 45°F): 1 to 2 weeks between feedings; can last up to 6 months
  • In the freezer (0° to 25°F): A year or more, but may take several feedings to revive
  • Maximum culturing temperature: 90°F


Active Sourdough Starter (rice flour)

  • At room temperature (68° to 78°F): 8 to 12 hours between feedings; can last up to 24 hours
  • In the refrigerator (40° to 45°F): 1 to 2 weeks between feedings; can last up to 6 months
  • In the freezer (0° to 25°F): A year or more, but may take several feedings to revive
  • Maximum culturing temperature: 90°F


Sourdough Bread

  • At room temperature (68° to 78°F): A week or two
  • In the refrigerator (40° to 45°F): Unopened, up to 6 months; opened and in a closed container, a month or more
  • In the freezer (0° to 25°F): Up to a year
  • Storage recommendation: Room temperature (2 to 3 days) or refrigerate (up to 2 months, sealed) or freeze (up to 6 months)

 

Sprouting Seeds


Sprouting Seeds

  • At room temperature (68° to 78°F):
  • In the refrigerator (40° to 45°F):
  • In the freezer (0° to 25°F):
  • Maximum culturing temperature: 90°F

 

Soy Cultures

Natto Spores

  • At room temperature (68° to 78°F): 3 to 4 weeks
  • In the refrigerator (40° to 45°F): 6 months or more
  • In the freezer (0° to 25°F): 6 months or more
  • Maximum culturing temperature: 105°F


Koji (Brown Rice or Barley)

  • At room temperature (68° to 78°F): about 6 months 
  • In the refrigerator (40° to 45°F) (recommended): 2 years
  • In the freezer (0° to 25°F): 2 years
  • Maximum culturing temperature: 105°F


Tempeh Starter Culture

  • At room temperature (68° to 78°F): 3 to 4 weeks
  • In the refrigerator (40° to 45°F): 6 months or more
  • In the freezer (0° to 25°F): 6 months or more
  • Maximum culturing temperature: 90°F

 

                                                
   
How Long Will Your Cultures Last?


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