Repitching limit?

[vin8n1]

Hey yeast experts, I am curious is there a limit to how many times one can repitch yeast at the homebrew level? I know commercial breweries have "house cultures" that they reuse. Do they just grow the yeast up after each brew and repitch indefinitely? Or do they have to order fresh batches from their supplier every so often? I know that yeast producers work off a pure slant to grow up massive batches and then save some of the fresh yeast as the new slant. Could one do the same thing at home?

 

[slayer021175666]

Sure, you CAN do the same thing at home but, I wouldn't. Look into "Top Cropping". And yes, the commercial guys have to go "back to the source" after a while too. It will mutate over time.

 

[DBhomebrew]

I bought a package of Imperial Pub last March. Since then I've brewed nine batches with it. The jar in the fridge is 4th generation.

Those were all harvested from finished beer. I now overbuild my starter and harvest from there.

Each homebrewer has their own level of cleanliness, sanitation, comfort, worry.

 

[odie]

there is no "standard". just repitch until you get something undesirable. start over.

the better your cleanliness...the more repitches you will get until it goes south.

 

[vin8n1]

Thanks for the great answers!

 

[hottpeper13]

I find that I get board brewing the same type and want different ones on tap so I will make an overbuild from the fridge and then repitch that up to 4 times. I don't keep track of the overbuild generations,and as long as the starter behaves the same I feel it's good to go.

 

[odie]

I find that I get board brewing the same type and want different ones on tap so I will make an overbuild from the fridge and then repitch that up to 4 times. I don't keep track of the overbuild generations,and as long as the starter behaves the same I feel it's good to go.

you can repitch repeatedly into different styles...so long as they are "compatible" with the previous style.

for example...I've been and still doing Marzen, Oktoberfest, Winter spiced lager, vienna, doppelbock, something else I can't recall...all with the same harvested yeast. Some have been dumps right on the old yeast cake.

 

[Dr_Jeff]

I saw a post somewhere where the person re-pitched on the same cake, not washing the fermenter for a year or more with no ill results.
I wouldn't feel comfortable with that, even though my cleanliness is as good as I can get it.

 

[AlexKay]

Sure, you CAN do the same thing at home but, I wouldn't. Look into "Top Cropping". And yes, the commercial guys have to go "back to the source" after a while too. It will mutate over time.

This. And "back to the source" ultimately means a culture stored under liquid nitrogen -- this could be on-site, off-site, or outsourced to someone else (e.g., White labs.) But above LN2 temperatures, yeast mutates surprisingly quickly, and there's no reason for it to mutate in ways that help brew quality.

 

[GrowleyMonster]

I have made several batches now from my house yeast. I harvest a couple of small samples, enough to innoculate quart starters. I make my starter the day before brew day and if it ever refuses to take off overnight in the starter, then I will pitch some dry BE-256 and start over again. If you always make the same beer this seems to work really well for quite a long time. Maybe indefinitely if cleanliness is good? I guess it depends on the yeast culture, the beer, and the environment. But if the yeast evolves, it will probably evolve to be stronger with that particular gravity and that particular fermentation temperature and that particular finished ABV.

As long as it works for you, it will work. When a batch tastes off, maybe start fresh with packaged yeast. Hey, it's only a few bucks, after all, and you can probably get another several generations from that modest purchase.

 

[slayer021175666]

I bottle harvest but, I don't have to stick to one style of beer. You can step up your yeast. Start with your lowest gravity beer then, switch to one that's a couple points above it and then finally, you can go for an eight or nine percent beer if you want.

 

[DBhomebrew]

Interesting stuff here...

https://www.homebrewersassociation.org/forum/index.php?topic=37475.0