Time to save money by washing or rinsing your beer yeast!
Want to save some money the next time you brew? One of the easiest ways Professional Brewers do this is by either washing or rinsing your yeast. Not only will you get a free pitch of yeast, but the new pitch will also have 2-3 times more yeast cells, giving you the confidence that you have the correct number of yeast cells for proper fermentation.
Most production facilities will harvest their yeast for up to 7 to 10 generations. We at Schoolhouse tend to try to use our favorite yeast strains for up to 7 generations. As for the typical homebrewer, we suggest keeping it around 5 gens (I know some of you go much farther), so if you think about the saving on a pack of 8 dollar yeast, that converts to roughly $1.06 per brew. WOW!
What’s the difference between rinsing and washing yeast?
Before re-pitching the yeast, brewers will either wash or rinse the yeast. Just like when you are cleaning and sanitizing during a brew, there is a big difference in these similar actions. Cleaning is excellent; you get rid of all the unnecessary dirt and debris. Sanitizing is the process of making sure that the environment you are using is completely free of all contaminants. So, think of rinsing the yeast as cleaning the yeast and washing the yeast as sanitizing the environment that the cells live. Both are entirely acceptable for repurposing the cells. It is entirely up to you which you prefer to do.
How to Rinse your Yeast
- Pour your harvested yeast from your fermenter into a sanitized container
- Make sure you have enough room for three times the space as the amount of the slurry (500ml slurry use a 2000ml container)
- Add distilled water in the slurry, leaving a little headspace
- Seal and shake the mess out of it
- Put the sealed container in the fridge and allow it to settle. You will get three layers.
- top is water
- the middle is viable yeast
- bottom is trub
- Let it sit for at least 24 hours.
- In one move, start pouring off the liquid from the top of the slurry
- When you get to the yeast layer, start pouring it into a smaller sanitized container that can be sealed.
- Get rid of the trub.
- Refrigerate till you need it for the next brew.
How to Wash Your Yeast
- Rinse the yeast first
- Make sure that your yeast stays between 30-45 degrees F
- You will need to determine how much slurry you need. (Each ml of slurry has approximately 7 billion cells) The amount of yeast you need is based on your specific gravity:
- Up to 1.050, you need 100 billion cells.
- 1.050-1.065 you need between 150-200 billion cells
- 1.065 you need 200-infinity cells (Make a ratio)
- About two hours before pitching the yeast, mix a food-grade phosphoric acid into the slurry, so the pH is between 2.2 and 2.5
- Maintain this pH for the next 90-120 mins constantly stirring (use a stir plate)
- Pitch those yeastie boys into your chilled wort
So, there you have it. Fresh yeast that can be used for your new batch of beer. I hope this helps and if you have any questions, just hit me up in the comments.
Check out Schoolhouse brewing recipes, and always feel free to order them from us or take them to your local homebrew shop. Cheers.