Yeast Storage Times Between Batches

How to Store Liquid Yeast Between Batches

Proper yeast storage is key to keeping it healthy, viable, and ready for the next fermentation. Poor storage can lead to low viability, slow fermentations, and off-flavors. Here’s how to do it right.

Step 1: Store Cold, But Not Too Cold

Best Temp Range: 1–4°C (34–39°F)

Do NOT freeze yeast! Freezing damages yeast cell walls, killing them.

• Most breweries store yeast in a dedicated yeast brink or sanitized container.
• If using a fridge, make sure it doesn’t dip below freezing.
• Storing too warm (>4°C) can lead to yeast metabolism issues and faster loss of viability.

Check daily: A sudden temp drop or spike can hurt yeast health.

Step 2: Keep It Sealed & Oxygen-Free

• Yeast should be stored in a closed, sanitized container to prevent contamination.
• Limit headspace to reduce oxygen exposure. Oxygen triggers premature aging.
• If yeast is stored in a brink, ensure CO2 pressure is low (too much can stress yeast).

Best Practices:

• Purge yeast brinks with CO2 before adding yeast.
• Store in a container with a one-way valve to prevent pressure buildup.

Step 3: Know Your Viability Window

Yeast loses viability over time. Here’s what to expect:

Best Practice: Use yeast within 3–7 days for best results.

Storage Time by Yeast Category

Notes:

• These timelines assume proper cold storage (1–4°C), sealed container, no oxygen exposure.
• The more sensitive the strain (like lager yeast), the shorter the window.
• Kveik and some Belgian strains can handle time, heat, and stress better, but may ferment slower after long storage.
• Always check viability if repitching after 5+ days - especially with lagers and clean ale strains.

Step 4: Check Before You Pitch

Before using stored yeast, check:

1. Smell – Fresh yeast should smell clean. A sour or rotten smell = possible contamination.
2. Appearance – Should be creamy and uniform, without significant hop or trub particulates.
3. Viability – Use a microscope and cell viability dye (such as erythrosin B) to check.

If viability drops below 80%, consider increasing your pitch rate and planning for a lab-fresh yeast pitch on the next generation.

Step 5: Wake It Up Before Pitching

Stored yeast can settle and go dormant. Before pitching:

• Let the container warm up slightly (but not above 10°C) before transferring.
• Give it a stir or shake to re-suspend cells evenly.
• If it’s been stored for over a week, oxygenate your wort well and consider extra nutrients to help yeast recover.

Summary: Storing yeast between batches

• Always store yeast cold (1–4°C) and sealed.
• Use within 3–7 days for best results, but many strains will store for up to 1 month.
• Check viability before repitching.
• Avoid oxygen exposure to extend shelf life.

By following these steps, you’ll keep your yeast strong and get consistent, high-quality fermentations.

How to Boost Yeast Storage Life with Nutrients & Oxygen

Healthy yeast stores better. Two key factors help:

1. Use Yeast Lightning (or Another Nutrient)

• Strengthens yeast cell membranes and nutrient reserves
• Helps yeast store energy for later
• Leads to better viability and faster, healthier fermentation after storage

Best Time to Add: Before fermentation, so the yeast can take up all the nutrients it needs to grow, divide, and conquer fermentation.

2. Oxygenate Wort Properly

• Helps yeast build strong membranes
• Improves fermentation performance
• Extends yeast viability in storage

O₂ Targets:

• Ales: 8–10 ppm
• Lagers: 10–12 ppm

Use a DO meter to ensure accuracy.

Additional Resources:

Check out our blog post entitled Yeast Storage Times Between Batches!