Money Saving Tips – Repitching Yeast
Wednesday, November 26th, 2008Update 11/12/2011: Check out the article on Bad Batches to see why you might want to avoid re-pitching yeast, or if you do so, make sure to understand the risks involved.
Did you know you can save ~10% on your next batch of home brew by re-pitching yeast? Some brewers buy new yeast for each batch. That is a good way to guarantee results provided the yeast is within the expiration date and has been refrigerated properly. However, at $7 a hit that comprises about 20% of the cost of the batch! With a little planning in terms of recipes and beer styles you can easily cut this in half or a third. It is a normal thing to do. The commercial breweries reduce their costs by repitching over and over.
Harvesting the yeast cake at the bottom of a finished primary fermentation vessel is easy. After siphoning off the beer into the secondary or bottling bucket the yeast will be left behind. Pour the yeast slurry (also called the yeast cake) into a sanitized container for safe keeping. You may need to loosen it up with some clean water. The yeast can be saved for several weeks in the fridge. It can be siphoned into regular 12oz bottles and capped, or put in a jar with an airlock.
The yeast can also be repitched immediately if you rack or bottle your old batch while you are cooling your new batch.
Do not repitch yeast that came from a contaminated batch, or had a weak or incomplete fermentation. Any yeast that had a healthy fermentation will work for this technique and it can be repeated many times. The maximum I have heard is ten times. That is getting up there and would limit choices of beer styles. Yeast can be a big factor in flavor and body. See a complete list of yeast strains by clicking here.
13 Responses to “Money Saving Tips – Repitching Yeast”
If you bottle the yeast, make sure to open it over the sink. My last one was really primed and it sprayed German lager yeast everywhere! The batch turned out fine, just a little unexpected cleanup.
I had it in the fridge for about 4 weeks before this had happened. Doh!
By Larry on Apr 6, 2009
I have been thinking about this for sometime and knew it could be done but I was afraid to try it myself. So yesterday I decided to give it a try and will be doing it today – Sunday – my brew day. I’m guessing I can pitch the whole cake? I’m pitching it straight from my 6 gal plastic conical fermentator which is very nice for this type of thing. I’ll let you know the results.
Andy
By Andrew van Hemert on Sep 13, 2009
I made two 5 gal batches today. One with a yeast pack the other from a yeast cake from previous batch. Same recipe.
Completely amazing. The yeast cake is already blowing like crazy. So far looks very good. The yeast back is active as well but not nearly as much as the yeast cake.
By Andrew van Hemert on Sep 13, 2009
This sounds good in theory unless your yeast has gone bad, as mine did, and I had bottled 4 batches before I discovered they all had the same problem, an oxidized phenolic “twangy” taste I think was due to the bad yeast used in all batches. Though I “saved 10%” I dumped out all 4 batches as nobody would drink it, a false savings. I’d say let the yeast guys make some money and buy new yeast each time. They provide a valuable service.
By Richard on Oct 6, 2009
Hi Richard,
Sorry to hear about your bad batches. We have all had a few go sideways, based on best intentions. I use this technique myself with success, as do many brewers and professional breweries.
The reasons for a bad batch could be many, including oxidation, quality of ingredients, water, fermentation temperature, sanitization, etc.
Were you taking gravity readings? I’d be interested to know the OG/FG, if the FG was low that means the yeast was probably healthy and temperature or other factors contributed to the problems.
If it were the yeast, then let’s check these conditions:
1) Did the yeast must come from a healthy batch?
2) Was the pitching rate must be high enough?
3) Did you make a starter?
This thread at HBT has some more info on the topic:
http://www.homebrewtalk.com/f163/storing-yeast-bottle-6-months-139787/#post1590463
By Larry on Oct 7, 2009
Hello,
Does any one have directions on cultivating the yeast before using it on a batch? My thought process is to buy two bags of liquid yeast. Use one on that weeks batch and then start culivating the other for future batches. I will need to know what to store it in, temps to keep it at, time frames, food for the yeast etc. I am willing to buy anything that it requires as my fiance just drop a boat load on our wedding and I feel I am justified on some “ME” spending :)
By Spiccoli on Jan 11, 2010
No need to buy two yeast packs. The easiest thing to do is simply save the yeast for next time as this page suggests by re-pitching or saving in the fridge in a sealed sanitized container. This means you need to get good at making yeast starters:
http://www.brewersfriend.com/2009/08/19/how-to-make-a-yeast-starter-og-1040/
I have been brewing now for over a year with the same strains of lager yeast and British ale yeast – no problems.
By Larry on Jan 11, 2010
Hi:
While a longtime home brewer, I an trying to reuse my yeast from my last batch for the first time. I washed back on 11/5/10, and then placed the contents in sterilized jars in the fridge. I created the starter on 12/21. The airlock on the starter became active after about 12 hrs. It is still active 12/23 am. I have about 1 inch of yeast cake on the bottom of the 64 oz fermenter and good foaming. How do I know if the started is good and ready? I have spent a lot of time searching the web and am in information overload without good answers to my questions. Any help would be greatly appreciated!
Mark
By Mark on Dec 23, 2010
It sounds like you made a healthy starter and are ready to pitch the yeast!
It usually takes at least 48 hours for my starters. I wait until the bubbling slows (about 2 days) or until it is nearly inactive (takes 3-4 days). I smell the yeast to make sure it is fresh (if it smells like dung, toss it). Then I decant off about half of the liquid, swirl the jar a few times, and pitch the slurry through a sanitized funnel.
By Larry on Dec 23, 2010
Usually I would estimate that I have 1 – 2 litres of sediment in the bottom of a batch.
Assuming that I siphon/drain this sludge into 330ml bottles and cap them (sanitized caps and bottles), then I have a few questions:
1) How long could these bottles be kept in the fridge before they become “dead”?
2) Can these bottles of yeast be used directly (i.e. let come to room temp, open the bottle, pour into new wort batch) into a fresh batch at some point in the future?
3) If they can be used directly, then how many of these 330 ml bottles of yeast would you suggest adding in order to get a speedy, healthy fermentation going?
4) If on the other hand, I was to make a starter for a single bottle of yeast sediment, would you reccomend stepping up slowly? Or would it be acceptable to use a bottle to prepare a single 2 litre starter?
By Peter on Mar 31, 2011
Hi Peter,
For reference to our readers, a 330ml bottle is a little less than a 12oz bottle. I’ve found it is much easier to use half pint ball jars (~230ml), which have a lid and screw cap.
To your questions:
1) My limit is six months. Once I used yeast that had been in the fridge for about 9 months. The batch had a mild off flavor I couldn’t pinpoint and I blamed the old yeast. It wasn’t horrible though.
2) Yes, if they are under 1-2 months old I do as you describe and pitch them directly without a starter. Usually the fermentation takes off rapidly.
3) One has been plenty for my batches.
4) I do a regular starter. I have not ‘stepped up’ my starters.
Best of luck!
By Larry on Mar 31, 2011
My experience:
Repitch five times
Harvest from the kraussen
Use starters
Use common sense, if a batch isn’t perfect start with new yeast
By David on Apr 5, 2012