Author Topic: Acid washing yeast, with Star San?  (Read 4514 times)

admin

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Acid washing yeast, with Star San?
« on: September 19, 2012, 09:35:43 AM »
Has anyone ever acid-washed yeast? The idea is that bacteria can't survive very acidic pH's, but yeast is unaffected.

It occurred to me yesterday that Star San if an effective sanitiser because it is an acid, and it's no-rinse as it doesn't kill yeast.

So, could yeast be acid washed with Star San solution?

Eoin

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Re: Acid washing yeast, with Star San?
« Reply #1 on: September 19, 2012, 10:07:07 AM »
Quote
Has anyone ever acid-washed yeast? The idea is that bacteria can't survive very acidic pH's, but yeast is unaffected.

It occurred to me yesterday that Star San if an effective sanitiser because it is an acid, and it's no-rinse as it doesn't kill yeast.

So, could yeast be acid washed with Star San solution?

Is it worth doing? I'm not sure it is personally. I don't think that star san is low enough pH, I understood pH2 is necessary to wash yeast, star san is in the pH +/-3 range. You could get some nitric or some hydrochloric and do it with that, but is it really worth it?

DEMPSEY

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Re: Acid washing yeast, with Star San?
« Reply #2 on: September 19, 2012, 10:52:44 AM »
All the stuff I read on this subject came up with,sterile distilled water,as the ideal for using to wash your trub.
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DEMPSEY

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Re: Acid washing yeast, with Star San?
« Reply #3 on: September 19, 2012, 11:13:56 AM »
I remembered this site before when researching this subject,http://www.birkocorp.com/brewery/white-papers/coming-clean-a-new-method-of-washing-yeast-with-chlorine-dioxide/
Dei miscendarum discipulus
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Eoin

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Re: Acid washing yeast, with Star San?
« Reply #4 on: September 19, 2012, 12:31:01 PM »
Quote
I remembered this site before when researching this subject,http://www.birkocorp.com/brewery/white-papers/coming-clean-a-new-method-of-washing-yeast-with-chlorine-dioxide/

Basically goes into washing but starts with the disputed nature of it's value.

I was told that it's only worth doing to save a valued strain that has problems.

oblivious

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Re: Acid washing yeast, with Star San?
« Reply #5 on: October 13, 2012, 08:08:03 AM »
Quote
Has anyone ever acid-washed yeast? The idea is that bacteria can't survive very acidic pH's, but yeast is unaffected.

It occurred to me yesterday that Star San if an effective sanitiser because it is an acid, and it's no-rinse as it doesn't kill yeast.

So, could yeast be acid washed with Star San solution?

Star san is a fundamental a detergent and this will
Destroy the lipid membrane of both bacteria and yeast. A food rade acid would be best

Jacob

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Re: Acid washing yeast, with Star San?
« Reply #6 on: October 13, 2012, 08:12:07 AM »
What about opinions on different sites saying that:
Quote
Starsan ends up as a yeast nutrient in the
fermenter'
?

Jacob

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Re: Acid washing yeast, with Star San?
« Reply #7 on: October 13, 2012, 09:34:16 AM »
I'm not going to argue about it but I've seen that on multiple sites...

oblivious

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Re: Acid washing yeast, with Star San?
« Reply #8 on: October 13, 2012, 09:54:49 AM »
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Very early to be up on a Saturday morning lads!
Because a one year old likes an early start  ;)

oblivious

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Re: Acid washing yeast, with Star San?
« Reply #9 on: October 13, 2012, 10:05:44 AM »
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I'm not going to argue about it but I've seen that on multiple sites...

Looks to.be true as star san break down it release phosphate and this is required for cell signaling and  phosphorylation of proteins, just like us


Just be awear that wild yeast and molds .can do the same too, so clean health year is.important

Spud395

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Re: Acid washing yeast, with Star San?
« Reply #10 on: October 13, 2012, 01:00:51 PM »
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You could get some nitric or some hydrochloric and do it with that, but is it really worth it?
Phosphoric acid is what is normally used in the brewing industry.
Like was stated above  pH2 is what is desired for between 2 and 4 hours.
Quiet a few of the big breweries acid wash as a matter of course, but it's very stressful for the yeast. IT will be more effective on ale yeast than lager yeast (I cant quiet remember why)

I really wouldnt bother, I'd look after my yeast better to begin with, it's only used when your yeast has a high bacterial count :o
« Last Edit: October 13, 2012, 01:13:36 PM by Spud395 »
Non modo......sed etiam

Partridge9

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Re: Acid washing yeast, with Star San?
« Reply #11 on: October 17, 2012, 01:59:53 PM »
Yeap -

A few misconceptions knocking around here -

Washing Yeast

- Its primarily done in Breweries to kill any bacteria - hold the pH at 2.4 for a period and the yeast with healthy cell membranes survive and the bacteria die. This will have the adverse effect of stressing your yeast - homebrewers shouldn't ever do this - if you have bacteria build up - buy new yeast !!! (like spud said!)

Rinsing Yeast

- Done by homebrewers with trub after a good healthy fermentation - collect trub - add sanitized water  - by a process of stratification - seperate the yuk and dead cells from the healthy yeast cells.

Stan San

- In normal concentrations will kill all yeast and bacteria but the reason you don't need to rinse after use is that by adding the beer you are lowering the concentration of starsan to negligible levels. The yeast may consume this but either way it does not impact the taste of the beer.

That's my understanding.

« Last Edit: October 17, 2012, 02:02:40 PM by Partridge9 »

Will_D

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Re: Acid washing yeast, with Star San?
« Reply #12 on: October 20, 2012, 06:35:33 PM »
The best two acids to use are: FG Phosphoric ( hard to get hold of ) or Citric Acid ( Easy peasy to GHO )

Footnote: To buy CA just don't look like a druggie in the health food shop. The one I was in said "We keep it round the back, out od sight", as druggies buy it; "to clean their needles"

FFS! no wonder we have an aids problem when the sensient IV users want to sanitise their kit and industry/shops make it difficult

/[endrant]
Remember: The Nationals are just round the corner - time to get brewing

oblivious

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Re: Acid washing yeast, with Star San?
« Reply #13 on: October 30, 2012, 09:07:43 PM »
Quote

Footnote: To buy CA just don't look like a druggie in the health food shop. The one I was in said "We keep it round the back, out od sight", as druggies buy it; "to clean their needles"

FFS! no wonder we have an aids problem when the sensient IV users want to sanitise their kit and industry/shops make it difficult/[endrant]


That or pro down to Thomas street and use the vinegar proved by some kind chippers (unaware) to clean them out ;)