Photo of an Imperial Yeast production facility.


A liquid yeast slurry used for the production of alcoholic beverages.

Typical Physical and Chemical Properties

Appearance: White to tan colored slurry

pH: 4.0 - 5.2
Density: ~1.0g/ml
Total Viable Cells/L: 1 x1012
Standard Viable Cells/ml: 1 x109
Concentrated Viable Cells/ml: Specific To Order

“Concentrated” Packaging

  • Some strains propagate to high cell densities.
  • To lower shipping costs, these strains may be packaged at concentrated levels (same total cells in less volume).
  • Contact us for specific packaged cell count (cells/ml.)

Typical Microbiological Properties

  • Colony morphology on WLN 
    • Consistent with the original mother culture.  
    • Single morphology.
  • Growth on UBA+ (aerobic and anaerobic)
    • Lawn growth
    • Less than 1 large or variable colored colony present per 1 X 108 culture cells.
  • Growth on WLN (aerobic and anaerobic)
    • Lawn growth
    • Less than (1) large or variable colored colony present per 1 X 108 culture cells.
  • Growth on LCSM for non-STA1+ strains (aerobic)
    • Less than 1 CFU per 1 X 108 culture cells
  • qPCR detection (Negative Results)
    • Saccharomyces cerevisiae var. diastaticus
    • Lactobacillus sp.
    • Pediococcus sp.
    • Hop resistant bacteria.
  • Positive results
    • Brettanomyces

Product Usage

Pitch Rate

Desired pitch rates may vary with fermentation conditions.
* Dial in your fermentation with our brewing calculators

Wort Volume (Bbl) Liters Pitched Pitch Rate (cells/ml)
1 0.5 5,500,000
1 1.0 11,000,000
1 1.5 16,500,000
1 2.0 22,000,000

Pitch Temp.

Directly add refrigerated yeast slurry to wort at the desired fermentation temperature.


Oxygenate wort to achieve a DO range of 15-25ppm DO.

Storage and Shelf Life

  • Store the cultures at or as close to 33°F as possible.
  • Do not freeze.
  • The shelf life is dependent on the strain and the storage temperature.
  • Use the yeast within 2 weeks of delivery.  
  • For longer storage, please contact customer service for guidance.


  • Rigid 1,2,4, and 8L food grade HDPE containers.
  • Volume per container dependent on order size.


Kosher Pareve


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