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General Category => Yeast and Fermentation => Topic started by: sdevries42 on April 04, 2014, 03:28:19 AM

Title: cold crashing process
Post by: sdevries42 on April 04, 2014, 03:28:19 AM
Can someone please explain the process of cold crashing and decanting yeast starter and the reasons for it?
Title: Re: cold crashing process
Post by: Stevie on April 04, 2014, 03:32:59 AM
When the starter has finished fermenting simply put it in the fridge for a day or more. Once all the yeast falls to the bottom, carefully pour off most of the spent wort. Leave enough to aid in swirling the yeast loose beige pitching.
Title: Re: cold crashing process
Post by: garc_mall on April 04, 2014, 04:06:52 AM
And the reason is that you don't want nasty oxidized starter wort in your beer.
Title: Re: cold crashing process
Post by: redbeerman on April 04, 2014, 04:24:59 PM
+(1+1)
Title: Re: cold crashing process
Post by: seefish on April 04, 2014, 04:45:55 PM
The reasoning is to allow the yeast to settle so that you can get rid of most of the liquid and just pitch the yeast.  However, if you don't have an enormous starter, like for a lager or high gravity beer, I have heard it is best to pitch the starter at high krausen so that the yeast are healthy and active when you pitch.  I don't remember the percentage rule of thumb for how much starter beer is ok to pitch into your wort, but if its a 1L starter for a 5 gal batch I will pitch the whole thing at high krausen.
Title: Re: cold crashing process
Post by: sdevries42 on April 04, 2014, 05:12:44 PM
Thanks for the info. I have been doing all 5 gallon batches so far and have not had a yeast starter greater than 5 gallons. Wasn't sure if I should be cold crashing or not.

Do you use mostly DME when making the starter? I read that your starter should match the sugar profile of the wort as the yeast adapt to the environment of the starter, and if these environments are not the same, this can inhibit fermentation. If so, how do you determine what to make the starter with?
Title: Re: cold crashing process
Post by: erockrph on April 04, 2014, 05:27:19 PM
Thanks for the info. I have been doing all 5 gallon batches so far and have not had a yeast starter greater than 5 gallons. Wasn't sure if I should be cold crashing or not.

Do you use mostly DME when making the starter? I read that your starter should match the sugar profile of the wort as the yeast adapt to the environment of the starter, and if these environments are not the same, this can inhibit fermentation. If so, how do you determine what to make the starter with?

Just about everybody uses plain DME. I wouldn't recommend using simple sugar in your starter, even if you will end up using some in the finished beer. Saccharomyces strains shouldn't have any problems consuming simple sugars, so there's no need to get them accustomed to them in your starter.
Title: Re: cold crashing process
Post by: tschmidlin on April 04, 2014, 05:53:43 PM
Thanks for the info. I have been doing all 5 gallon batches so far and have not had a yeast starter greater than 5 gallons. Wasn't sure if I should be cold crashing or not.

Do you use mostly DME when making the starter? I read that your starter should match the sugar profile of the wort as the yeast adapt to the environment of the starter, and if these environments are not the same, this can inhibit fermentation. If so, how do you determine what to make the starter with?

Just about everybody uses plain DME. I wouldn't recommend using simple sugar in your starter, even if you will end up using some in the finished beer. Saccharomyces strains shouldn't have any problems consuming simple sugars, so there's no need to get them accustomed to them in your starter.
Right, there will be no issue for the yeast to ferment sucrose or glucose, they don't need to get used to it.  DME is the way to go for starters.