Er1A Malolactic Bacteria | Wyeast 4114 | Oenococcus oeni
Wyeast 4114 Er1A malolactic bacteria for red wines and low-pH MLF
Wyeast 4114 Er1A is a fresh liquid Oenococcus oeni malolactic culture for home winemaking. It converts sharper malic acid into softer lactic acid, helping high-acid wines finish with a rounder, smoother acid profile.
Er1A is the more targeted red-wine strain in Wyeast's home malolactic lineup. Wyeast notes that it was isolated for tolerance to low-pH conditions and lists it as an excellent choice for red wines. Use it when the wine needs malic acid reduction but you want a strain selected for red-wine cellar work rather than the broader all-purpose blend.
Best fit
- Recommended use: red wines and high-acid wines where malolactic conversion is desired.
- Culture: liquid Oenococcus oeni in a sterile, organic juice-based nutrient medium.
- Temperature range: 70-90°F / 21-32°C.
- Alcohol tolerance: 12-18% ABV.
- Typical conversion time: Wyeast lists malolactic conversion as generally complete within 1-3 months.
- Package size: one home winemaking pouch inoculates 6 gallons / 22 L of must or wine.
How 4114 compares with 4221 and 4007
Choose 4114 Er1A when you want the red-wine, low-pH specialist. Choose Wyeast 4221 Ey2d when you are working with white wines or cooler cellar temperatures. Choose Wyeast 4007 Malolactic Blend when you want the broadest culture option for wine, cider, or mead and do not need to isolate the red-wine or cool-cellar strain.
| Culture | Best use | Temperature range | Why pick it? |
|---|---|---|---|
| Wyeast 4114 Er1A | Red wines and low-pH conditions | 70-90°F / 21-32°C | Targeted red-wine strain selected for low-pH tolerance. |
| Wyeast 4221 Ey2d | White wines and cooler cellars | 55-70°F / 13-21°C | Suggested by Wyeast for white wines and selected for low cellar temperatures. |
| Wyeast 4007 Blend | Wine, cider, and mead | 55-95°F / 13-35°C | Broad blend for a wider range of temperature and pH conditions. |
How to use Wyeast malolactic cultures
Keep the pouch refrigerated at 34-40°F / 1-4°C and do not freeze it. Before use, let the pouch come to room temperature, sanitize the outside of the package, shake well, then pour into 6 gallons / 22 L of wine, must, or juice that has completed or nearly completed alcoholic fermentation. Wyeast also allows co-inoculation once primary fermentation has begun.
Free SO2, alcohol, pH, temperature, and nutrient status can all affect malolactic fermentation. For the cleanest result, confirm the wine is in a suitable range for the culture and monitor malic acid reduction instead of relying on the calendar alone.
Fresh-culture handling
Liquid malolactic cultures are temperature-sensitive. We store Wyeast cultures cold at SoCal Brewing Supply, and for shipped orders we recommend adding an ice pack to reduce temperature shock during transit.