Do you think that Starsan might contibute to oxidation in kegs?

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Reelale

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Looking for opinions. I know we all go to great lengths to keep oxygen exposure to a minimum on finished beer. We rack gently, flood the kegs with CO2 to purge O2 out, and make sure that dry-hopping doesn't introduce unwanted O2. We also try to minimize O2 exposure during recirculation, although HSA might not even be an issue. We've been told to "not fear the foam". But I get a lot of foam when I am sanitizing my kegs. That foam contains air bubbles which are full of O2. I'm racking on top of this foam. Just wondering......
 
Looking for opinions. I know we all go to great lengths to keep oxygen exposure to a minimum on finished beer. We rack gently, flood the kegs with CO2 to purge O2 out, and make sure that dry-hopping doesn't introduce unwanted O2. We also try to minimize O2 exposure during recirculation, although HSA might not even be an issue. We've been told to "not fear the foam". But I get a lot of foam when I am sanitizing my kegs. That foam contains air bubbles which are full of O2. I'm racking on top of this foam. Just wondering......

A good observation and a good question but, why are you racking "on top" of the foam?

I still take efforts to ensure little to no splashing in the keg and basically float the foam on the liquid surface. And I have never purged the keg prior to racking.
 
I don't think it's enough to worry about. When I rack the Starsan floats to the top and is released when I purge the keg......hopefully. Thanks, now you've given me something else to fret about. Lol
 
A good observation and a good question but, why are you racking "on top" of the foam?

I still take efforts to ensure little to no splashing in the keg and basically float the foam on the liquid surface. And I have never purged the keg prior to racking.

I meant that I am racking while there is a lot of foam still in the keg. No splashing. And yes the foam floats on the surface. I guess my question is what happens to that captured 02? Just wondering....
 
I don't think it's enough to worry about. When I rack the Starsan floats to the top and is released when I purge the keg......hopefully. Thanks, now you've given me something else to fret about. Lol

That's what I thought too. But I'm not so sure, seems like the foam breaks down as it contacts the beer, at least on top. There has to be 02 in solution, or is there? I'm trying to track down and eliminate a persistent source of mild oxidation in my kegged beer. I may be grasping at straws.
 
hmmmm....

Maybe switch to Iodophor for sanitizing to a bit to eliminate/confirm this variable?

That would answer the question.

Or, maybe even try a CO2 purge after the foam. It should at least cause the O2 in the foam to rise from the occasion. Then rack within the blanket.
 
What would be there if the foam wasn't there? Air. I doubt the O2 in the foam gets absorbed into the beer any more than the O2 from the straight air.
-Jeff
 
My kegs are usually purged and sanitized before I start, but I always splash around some more star-san before racking. So, I suppose, my bubbles are filled with CO2. If it worries you, purge before sanitizing.
 
What would be there if the foam wasn't there? Air. I doubt the O2 in the foam gets absorbed into the beer any more than the O2 from the straight air.
-Jeff

That's a good point. I'm not sure if the O2, being encapsulated, behaves differently than the gaseous, free O2 we try to purge. Or even if it goes into solution at all.
 
The bubbles aren't O2. They are atomospheric air, which is 20% oxygen.
Don't shake your keg and you won't be mixing any of that air into the beer. It takes agitation to dissolve gas into liquid at any decent rate..
 
All I can suggest is go through your process and look for the most likely culprit even if it is Star San. It might be something obvious.

I almost slapped my forehead when I realized that I was putting my kegs into the Keezer without purging them first... It really doesn't do much good to wait until you've shaken them to purge the headspace ;)
 
The bubbles aren't O2. They are atomospheric air, which is 20% oxygen.
Don't shake your keg and you won't be mixing any of that air into the beer. It takes agitation to dissolve gas into liquid at any decent rate..

Yes, I realize this. But it is 02 nonetheless, and it's in the keg when it is capped. We try to eliminate all sources of air contact with finished beer. I guess the question is even if you purge the keg, will this percentage remain in the beer? I'm not convinced it doesn't.
 
I posed this same question here
https://www.homebrewtalk.com/f11/starsan-fear-rather-dont-fear-199000/#post2318143
Glad some body actually answered the question.

I did a search before I asked, and couldn't find that thread. But, I just checked your linked thread and I don't think anyone really answered the question. There is 02 in the foam, that foam stays in the beer when you rack into the keg. The question remains....does this contribute to oxidation? Starsan being food for yeast really has no bearing here, this is finished beer that will be cold-conditioned and/or carbed.
 
In that thread I asked
"But explain to me how the air in star san bubbles won't introduce oxygen into the beer? I mean there is air in the foam the foams in the beer , so the air is in the beer."
My point was people tried to answer your question, where I was just called "ignorant and paranoid"
 
In that thread I asked
"But explain to me how the air in star san bubbles won't introduce oxygen into the beer? I mean there is air in the foam the foams in the beer , so the air is in the beer."
My point was people tried to answer your question, where I was just called "ignorant and paranoid"

I saw that. Some folks, very knowledgeable people, can sometimes seem rather abrasive at times. I still think your original observation is valid, and deserves a definitive answer....if there is one. I'm having a persistent mild oxidation problem that happens late.....I'm trying to run all variables to ground.
 
I think you are over thinking this issue, not that it is always a bad thing. There is air in the keg whether or not it is in a bubble. Just sit back and enjoy your beer - all will be ok.
 
I think you are over thinking this issue, not that it is always a bad thing. There is air in the keg whether or not it is in a bubble. Just sit back and enjoy your beer - all will be ok.

Probably. Just curious I guess. If it's something that has an effect, and we can control it, why not? Maybe Starsan is better suited for pre-fermentation sanitation more so than bottling and/or kegging.....I don't know.
 
I think this is an interesting question, but I am the paranoid ignorant type and my yeast don't need food in the keg.

I think there are a lot of reasons to use a non foaming sanitizer in kegs. I tend to clean and sanitize kegs in batches of 5 or so (I have twenty some) and I fill the first keg with a non foaming sanitizer (I use an iodophor) and then push to each subsequent keg. That leaves them purged, sanitized, and foam free. That process would be impossible with a foaming sanitizer as it would foam endlessly in the line on transfer. You can use the non foaming version of star-san (saniclean) if you want, but my tiny ignorant mind likes the idea of using sanitizers with different mechanisms in my brewery. I feel that reduces my chances of harboring something that is resistant to one of them.
 
Two batches, back to back, bottle conditioned and bottles sanitized with iodophor. No noticeable oxidation. Dunkelweizen on the keg, sanitized with starsan. I let this one age a bit in the kegerator sans gas, but did purge it prior to fill. I can taste oxidation. I know I introduced another variable by not immediately carbonating. Still working on it. This is driving me crazy. Next step is iodophor, carbonate immediately. I'll report back.
 
If you happen to have two kegs and a few empty bottles for the next time, it would be a good experiment to do all three processes (Keg with starsan, bottle & keg with iodophor) in parallel with the same fermented beer. Yeah probably too much fuss, but seeing that you are trouble shooting to find something that is driving you crazy, you might try it.

I'd be interested to follow along. Good luck.
 
Two batches, back to back, bottle conditioned and bottles sanitized with iodophor. No noticeable oxidation. Dunkelweizen on the keg, sanitized with starsan. I let this one age a bit in the kegerator sans gas, but did purge it prior to fill. I can taste oxidation. I know I introduced another variable by not immediately carbonating. Still working on it. This is driving me crazy. Next step is iodophor, carbonate immediately. I'll report back.

Are you naturally carbonating in the keg or are you carbing with gas? Personally, I think the natural carbonation process reduces the chances of oxidation being a problem.
 
If you happen to have two kegs and a few empty bottles for the next time, it would be a good experiment to do all three processes (Keg with starsan, bottle & keg with iodophor) in parallel with the same fermented beer. Yeah probably too much fuss, but seeing that you are trouble shooting to find something that is driving you crazy, you might try it.

I'd be interested to follow along. Good luck.

I'm open to all recommendations at this point.

Are you naturally carbonating in the keg or are you carbing with gas? Personally, I think the natural carbonation process reduces the chances of oxidation being a problem.

I'm force carbing with and purging. I don't see the difference in relation to my problem though.
 
I'm force carbing with and purging. I don't see the difference in relation to my problem though.

When you carb naturally, you have another fermentation that takes place within the bottle/keg. Yeasts use O2 to reproduce before fermentation. Carbonating naturally can scrub O2 from your beer.

Try naturally carbonating one of your kegs and see if you have the same problem.
 
When you carb naturally, you have another fermentation that takes place within the bottle/keg. Yeasts use O2 to reproduce before fermentation. Carbonating naturally can scrub O2 from your beer.

Try naturally carbonating one of your kegs and see if you have the same problem.

Ah...makes sense now. I'll try this next one.
 
Heres a crazy idea, but when your sanitizing the keg hook up the gas to the outlet and make CO2 filled bubbles, as the foam rises it purges the keg from bottom up.


I posted about this before revvy & his fanboys got all worked up and thought it was foolish.
> Posted by Revvy:
because, quite frankly it's not really necessary
.

https://www.homebrewtalk.com/f163/purging-secondary-156065/

Not so foolish is it? spend all that time - money only to get oxidation in the beer.
 
When you carb naturally, you have another fermentation that takes place within the bottle/keg. Yeasts use O2 to reproduce before fermentation. Carbonating naturally can scrub O2 from your beer.

Try naturally carbonating one of your kegs and see if you have the same problem.

Yeast don't reproduce if you bottle carb with dextrose or sucrose as you are adding no additional nitrogen. They would if you added malt extract or otherwise added a nitrogen source. Regardless, yeast are reductive whether or not they reproduce. In practice, yeast will reduce about 60% of the oxygen in the headspace of a bottle. This is why essentially every modern brewery that bottle conditions pre-evacuates the bottles with co2.
 
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