Malolactic Cultures for Home Enthusiasts


Wyeast Premium Liquid Yeast and fermentation products have been the choice of professional winemakers, cidermakers, meadmakers, and more since 1986, and we have offered the same quality and diversity of cultures to home enthusiasts since then, too.

Our malolactic cultures will provide rapid and complete malic acid reduction in high acid wines. Malic acid reduction will balance and soften wine while enhancing flavor and aroma characteristics including vanilla and buttery notes. Malolactic conversion is generally completed within 1-3 months. Er1A is an excellent choice for red wines, it was isolated for it tolerance to low pH conditions. Ey2d is suggested for white wines, it has been selected for it tolerance to low cellar temperatures. 4007 Blend will cover a broad range of temperatures and pH conditions.



125 mL Malolactic bacteria slurry (Oenococcus oeni


A liquid suspension of Oenococcus oeni grown in a sterile organic juice based nutrient enriched medium. 


Instructions for the proper use of Malolactic packages:
  1. Remove from refrigeration (34-40 °F, 1-4 °C) and allow to come to room temperature just prior to use.
  2. Shake well and sanitize package.
  3. Open and pour into 6 gallons (22 L) of wine or must that has completed or nearly completed alcoholic fermentation, or add once primary fermentation has begun. Free SO₂ levels should be less than 15 ppm.
  4. Maintain fermentation or cellaring temperature recommended for the ML strain. Malolactic fermentation is generally complete within 1-3 months.

Er1A should be between 70 °F to 90 °F (21-32 °C)

Ey2d should be between 55 °F to 75 °F (13-24 °C)


Sterile Packaged Product – UV Light Barrier –  Guaranteed 

Keep Refrigerated. Do not freeze.

Best if Used by:

This package performs best when used by the Best if Used By date when stored between 34-40 °F (1-4 °C). Older malolactic cultures that have been exposed to higher or lower temperatures may perform slowly.


Product Warranty

Our Product Warranty states that we guarantee the viability of the product in our Malolactic culture packages for a minimum 6 months assuming that they have been properly shipped, stored and handled. Our superior packaging material provides 100% oxygen barrier and UV light protection making this exceptional guarantee possible. During the shelf life, some loss of viability is to be expected.

Malolactic culture packages will sometimes swell slightly to moderately during shipping or later while properly stored. This is not an indication of deterioration if the package is within the Best if Used By date and has been properly handled. This is result of trace amounts of nutrients, still available at the time packaging, causing small amount of culture activity and CO₂ production.