Wyeast Liquid Cultures for

Wild & Sour homebrewing

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Keep refrigerated. These cultures are fresh.

Let's get brewing

Wyeast is a home-brewed, family-owned business located in the heart of Oregon’s scenic Columbia River Gorge. Established in 1986, our mission is to inspire homebrewers by providing fresh, pure, pitchable liquid yeast & cultures.

This package contains fresh liquid wild & sour cultures, providing unlimited opportunity for creative fermentation.

Find your

Pitch Rate

For more advanced homebrewers. Pitch rate is based on your beer style, species, fermentation phase (primary or secondary), fermentation temperature, and desired outcome. Learn more about:

Pitch Rates

Wild & Sour Brewing

Kettle Souring

  • For Blended Cultures

  • For Brettanomyces yeast

  • For Lactobacillus & Pediococcus bacteria

Ready to Brew



Remove from refrigeration. Allow package to come to room temperature (70 °F or 21 °C) just prior to use.


Sanitize the package before opening.


Give the package a good shake, tear it open, and pour into 5 gallons (19 L) of unfermented wort or fermented beer.


Adjust conditions to your desired fermentation temperature for the strain. Note, these cultures typically perform best at temperatures of 68 °F (20 °C) or higher.

Select your

Fermentation Temperature

Adjust your fermenter to your desired temperature for the culture. Fermentation temperature influences the activity of the yeast and bacteria, the characteristics produced during the fermentation process, and the rate at which souring will develop.

  • Wild & Sour Fermentation Temperatures

More Information

Product Description

A liquid suspension of Premium Liquid Yeast and bacteria cultures grown in sterile, nutrient-enriched medium.

Wyeast’s Premium Liquid Yeast & Cultures for Homebrewing includes Saccharomyces cerevisiae, Saccharomyces cerevisiae var. diastaticus, Brettanomyces yeast, Lactobacillus lactic acid bacteria, Pediococcus lactic acid bacteria, and blends of two or more of these species in our Blended Cultures. Products containing S. cer. var. diastaticus are identified on the front of the package with “STA1 +”, the signature gene of diastatic yeast.

  • Sterile Packaged
  • UV Light Barrier
  • Keep Refrigerated
  • Do Not Freeze

Best By Date

This product performs best when used by the Best By date when stored between 34-40 °F (1-4 °C) and used following the instructions here. We calculate our Best By date according to the true age of the yeast and bacteria as determined by our microbiologists, and not simply by the date the product was packaged. This method provides consistent, reliable Best By dates and a minimum of 6 months of shelf life under our product warranty.

Packages close to the Best By date and packages that have experienced temperature fluctuation may take more time to begin fermentation. It is recommended to pitch an additional package if the product is within 60 days of the Best By date. Do not make a starter for blended cultures.

Product Warranty

We guarantee the integrity of our yeast & cultures for a minimum of 6 months, assuming they have been properly shipped, stored, and handled. Our packaging material provides 100% oxygen barrier and UV light protection making this guarantee possible. During the guaranteed shelf life, some loss of viability is to be expected. This will vary from one strain to another. However, the rate of viability loss is significantly less than many outside sources claim.

Packages will sometimes swell slightly during shipping, or later while properly stored. This is not an indication of deterioration if the package is within the Best By date. This is due to trace amounts of residual fermentables at the time of packaging being consumed by very active yeast. The cells produce some CO2 during this process, also known as “off gassing,” and cause the package to swell. Some strains are more prone to this than others.

Intended Use

This product is designed and intended for home-scale fermentations and is not warranted for the use in commercial application beyond pilot testing. This product is not for propagation or remanufacturing.

Certified Kosher

All Wyeast Laboratories, Inc. products are certified Kosher by the Orthodox Union.

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