Overpitching Yeast

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Slid

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Problems are said to include over-attenuation and lack of esters, which can be produced in greater quantity with a slight under-pitch.
 

Alan_Reginato

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This article suggests that occurs an increase in diacetyl for high pitch rate. [PDF] Impact of pitching rate on yeast fermentation performance and beer flavour | Semantic Scholar
The threshold should be around 100 ppb, and with 40x10^6 cells/mL in a lager, hit 307 ppb.
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I usually pitch 5x10^6 cells/mL, with dry yeast. That's the minimum suggested by Brewers Friend calculator. For 0.35M cells / mL / °P

Maybe with 1 L slurry for 20 L wort, could get 50x10^6 cells/mL.

Thinking about, I just realized that my last batch, that I used the yeast cake from the previously one, hit that number. I didn't notice anything that seems to be an off flavour. But it's something to care about next time.
 

Hazelwood Brewery

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Looking for views please on why you should not over pitch yeast
What are you trying to achieve by over-pitching?

If you’re looking to shorten fermentation time for example you might want to consider the yeast you use, the temperature you ferment at, or prepare a starter to reduce lag time and increase cell count.
 

Obadiah Boondoggle

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What are you trying to achieve by over-pitching?

If you’re looking to shorten fermentation time for example you might want to consider the yeast you use, the temperature you ferment at, or prepare a starter to reduce lag time and increase cell count.
My question wasn't to try and achieve anything in particular

It's just I have read "don't under or over pitch"

I understand the under pitching consequences but not so sure on over pitching athumb..
 

Hazelwood Brewery

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My question wasn't to try and achieve anything in particular

It's just I have read "don't under or over pitch"

I understand the under pitching consequences but not so sure on over pitching athumb..
Understood athumb.. I also sometimes just want to know stuff.
 

Cheshire Cat

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I'm currently brewing a Munich Helles with CML Hell yeast. Last time I made it I pitched two packets and fermented at 12C as per the instructions on the packet. It turned out very good. I intend to do the same today.
 

Obadiah Boondoggle

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This article suggests that occurs an increase in diacetyl for high pitch rate. [PDF] Impact of pitching rate on yeast fermentation performance and beer flavour | Semantic Scholar
The threshold should be around 100 ppb, and with 40x10^6 cells/mL in a lager, hit 307 ppb. View attachment 42566

I usually pitch 5x10^6 cells/mL, with dry yeast. That's the minimum suggested by Brewers Friend calculator. For 0.35M cells / mL / °P

Maybe with 1 L slurry for 20 L wort, could get 50x10^6 cells/mL.

Thinking about, I just realized that my last batch, that I used the yeast cake from the previously one, hit that number. I didn't notice anything that seems to be an off flavour. But it's something to care about next time.
Thanks, Alan

Really useful article
 

aamcle

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Unless you're brewing something that requires under pitching yeast to deliberately stress it homebrewers are hardly likely to have a problem. Commercial breweries use vast amounts of yeast and make good beers.
If you ask here, may need a new thread, about pitching on the Yeast cake you will find few problems or off tastes reported.


Aamcle
 
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