Home Brew Yeast Harvesting & Repitching Guide

Guide yeast harvesting, washing, storage, and repitching for multiple batches based on yeast type, beer style, and health to save money and build house flavors.

‍

Building house character and general yeast harvesting guidance.

‍

We ask for yeast type, generation number, beer style, harvesting method, storage method, current problem, and experience level because these allow safe repitching. Limitation: the tool uses general viability. Mutation risk increases after 5-10 gens. Make starters to check health.

‍

Yeast Harvesting Guide

Brought to you by TheToolCollective.com

Overview

This guide will help you successfully harvest, store, and repitch yeast from 1st generation liquid yeast (Wyeast/White Labs) for clean lager or ale fermentation. We’ll cover the washing method, storage in a fridge slurry, and provide insights on mutation and viability.

Step-by-Step Yeast Harvesting

1. Washing the Yeast

• a. Collect the Slurry: After fermentation, collect the yeast slurry from the fermenter. Pour it into a sanitized container.
• b. Add Water: Add an equal volume of sterile water to the yeast slurry. This helps to dilute the sediment and separate the yeast from the trub.
• c. Swirl: Gently swirl the mixture to suspend the yeast. Avoid vigorous shaking to minimize cell damage.
• d. Let Settle: Allow the mixture to sit for approximately 10-15 minutes. The heavier trub will settle at the bottom while the yeast will remain suspended in the liquid above.

2. Decanting the Yeast

• a. Pour Off Liquid: Carefully pour off the top liquid, which contains the yeast, into another sanitized container. Leave the trub behind.
• b. Repeat Washing: If desired, you can repeat the washing process with fresh sterile water to further purify the yeast.

3. Storage in Fridge Slurry

• a. Store in Containers: Transfer the washed yeast into sanitized containers. Label them with the strain and date harvested.
• b. Refrigerate: Store the containers in the fridge at around 34-40°F (1-4°C). This will help maintain yeast viability.

4. Repitch Amount

• a. Calculate Repitching Volume: For a typical homebrew batch (5 gallons), you can repitch approximately 1-2 cups of slurry from your fridge.
• b. Adjust for Batch Size: For larger or smaller batches, adjust the amount of yeast accordingly.

Understanding Mutation and Viability

Mutation

• Yeast can mutate over generations, affecting flavor, fermentation efficiency, and other characteristics.
• While 1st generation yeast is typically stable, repeated repitching can lead to mutations that may alter your brew’s profile.

Viability

• Viability refers to the proportion of yeast cells that are alive and capable of fermentation.
• A healthy slurry should have a viability of 80% or higher. You can assess this with a microscope or a viability count kit.

Conclusion

By following these steps, you can successfully harvest and store yeast for future use while maintaining its viability and minimizing mutation risks. Happy brewing!

Brought to you by TheToolCollective.com

‍

The Tool Collective are a multi talented group of passionate hobbyists on a mission to create highly useful and intelligent decision making tools to help others who share our passion and interests. Home brewing is a new hobby for a few of us, in addition to our already passionate cooking/gardening crowd. Being able to craft your own style of beer or wine is truly a self fulfilling hobby and one you can certainly impress your friends and family with. Not to mention the home brew community is large and growing exponentially, so we decided to make a big batch of decision tools for this community to help level-up their setups and master their craft. Enjoy, and happy brewing!

‍

Made with The Tool Collective's signature model. We combine an AI engine which process the user's input choices and runs it through our specifically designed logic and reasoning parameters for that tool to curate a precise and organized output. An enthusiast knowledgeable in the tool category designs the tools inputs and input choices, writes custom logic parameters, and defines the output format and requirements. The AI engine powers the system and creates a lightning fast, highly intelligent decision tool, which is always up-to-date with current pricing and publicly available information on whatever the tool is designed for. Combines all of the internets resources into one.

‍