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Oxygen "Absorbing" Caps

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So for the folks that HAVE to sanitize their caps...... Just have dip your caps in sanitizer right before placing them on the bottle. This way they are sanitized and activated. Problems?

As long as you are leaving enough time for the sanitizer to work before it potentially touches your beer. (~30sec-1minute for most).
 
As long as you are leaving enough time for the sanitizer to work before it potentially touches your beer. (~30sec-1minute for most).

I thought about that. If you dip it in the sanitizer, set it it on the bottle, and cap it, shouldn't the sanitizer do it's job on both the cap and the rim of the bottle even if it is immediately placed on the bottle? Providing you don't tip the bottles within 30 seconds or a minute?
 
Really good discussion in this thread. I was searching for this because I was listening to the recent Brewing Network Sunday Session about bottling and some of those dudes were advocating using oxy caps without sanitizing. They made the point that it is crucial to clean and sanitize bottles, but the caps come very clean and shouldn't present any contamination issues if handled properly.

I have no specific opinion on whether or not you should sanitize your caps, but I plated swabs from a few caps a while back. Two stayed clean, one showed mold contamination, and one showed both mold and bacteria. They ain't that clean :D

Whether or not that would impact a beer is of course a different question. I've done entire batches forgetting to sanitize bottles, carboys, tubing, and just about everything else we're supposed to sanitize and didn't have an obvious infection. Then again, I've also had a gusher or two over the years.

As others have mentioned, the O2 absorption happens over hours and days, not minutes. I clean everything else, and I'm not sure what the downside is to sanitizing caps. It just strikes me as a brewing "best practice" (to borrow science jargon).

And of course, there's a lot of middle ground between perfect sanitation and raging infection. Just because you don't get bottle bombs doesn't mean that your beer wasn't (perhaps only slightly) negatively impacted by cap-borne intruders. Then again, that doesn't mean it was, either. At the end of they day, everybody has their own sense of how much trouble quality control is worth. :mug:
 
I thought about that. If you dip it in the sanitizer, set it it on the bottle, and cap it, shouldn't the sanitizer do it's job on both the cap and the rim of the bottle even if it is immediately placed on the bottle? Providing you don't tip the bottles within 30 seconds or a minute?

My current procedure is to just place a non-O2-absorbing cap (sanitized for a long time) loosely on top of the bottle as soon as I fill it. When I'm done filling the entire batch, I then press the caps on. The theory behind this is that just loosely placing the cap on the bottle keeps stuff from coming in, while allowing CO2 coming out of solution in the bottle to push the O2 out (CO2 being heavier than O2?). So by the time I cap, it's mostly CO2 in the headspace.

Under this scenario, using O2-absorbing caps, I could wait until I fill the bottle to quickly dip the cap in the sanitizer (Star San). By the time I actually press the cap on, both the cap and the neck have had enough time for the sanitizer to act.

Anything wrong with this?
 
This seems to be the most "official" O2-absorbing thread I could find on HBT. Nice to hear the manufacturers recommendations.

Two points for posterity for this zombie thread:

* There are field reports of decreased carbonation from using these[1]. Can anyone comment?

* Funny enough, most styles meant for long aging actually benefit from o2 exposure (e.g. barleywine with the sherry notes) , or have enough melanoidan antioxidants to be fine anyway (e.g. imperial stout). The only real use-case I've heard of is in slowing the loss of hops flavors/aroma, but I still haven't seen much evidence one way or the other for this...

[1] http://www.northernbrewer.com/shop/review/product/list/id/210/category/22/
 
My current procedure is to just place a non-O2-absorbing cap (sanitized for a long time) loosely on top of the bottle as soon as I fill it. When I'm done filling the entire batch, I then press the caps on. The theory behind this is that just loosely placing the cap on the bottle keeps stuff from coming in, while allowing CO2 coming out of solution in the bottle to push the O2 out (CO2 being heavier than O2?). So by the time I cap, it's mostly CO2 in the headspace.

Under this scenario, using O2-absorbing caps, I could wait until I fill the bottle to quickly dip the cap in the sanitizer (Star San). By the time I actually press the cap on, both the cap and the neck have had enough time for the sanitizer to act.

Anything wrong with this?

Old thead, but interesting. I assume you are bottling from a keg then, since i don't think you will get too much CO2 from flat beer while your botteling.
 
I have heard recently that there are actually negative effects from using these caps but I haven't heard any real explanation why. Since they absorb it's possible that they might absorb CO2 and make the beer less carbed. Also, I am assuming that they might absorb hop aromas too? Again just brainstorming here.
 
I have heard recently that there are actually negative effects from using these caps but I haven't heard any real explanation why. Since they absorb it's possible that they might absorb CO2 and make the beer less carbed. Also, I am assuming that they might absorb hop aromas too? Again just brainstorming here.

Most probably the OXY caps contain the same, or similar, chemical (iron) as standard oxygen absorbing packets used for food preservation. These packets include some water to allow the chemical oxidation reaction (formation of rust) to take place and are sealed airtight to prevent the reaction from beginning until they are opened and the contents (iron and water) are exposed to oxygen.

Quote from patent " an oxygen absorbing layer consisting of an oxygen absorbent dispersed in a resin."

Unlike the food storage packets which also contain a small amount of water the oxy-caps use DRY iron which must first be moistened to become activated, thus they must be wet first. The reaction is also SLOW so the few minutes they spend in a sanitizer should not have any real effect on them.

The following is OMO.

They absorb OXYGEN and nothing else. As long as your bottles are stored upright the beer does not contact the absorbant layer for any length of time there should be no problems with off flavors from the cap.

bosco
 
I just want to say that thank god the alcohol doesn't kill everything because if it did, we wouldn't have bottle fermentation cuz the alcohol would kill the yeast.

Also about capping the bottles and then tipping them upside down to wet the cap to activate it, wouldn't that help the oxygen absorb into the beer helping it to oxidize quicker?

Think I'll continue my old practice of sanitizing the caps.
 
I have also wondered about the inverting since I would agree that it would let some of the 02 into the solution. I have always sanitized my caps, seems to me it's not worth the risk to not do it. I know this has been thoroughly discussed in this thread but it's just MHO.
 
Welp... I guess I won't be sanitizing or soaking my 02 absorbing caps anymore!! Wish I read this thread yesterday when I bottled 5 gallons of DIPA with two dryhop stages.
 
i don't really agree with no sanitizing. i don't think the reaction of those caps happens in seconds. also no pro breweries that i know of use those caps so i don't think it's that crucial/makes that much of a difference. it would be interesting if someone on here capped half their batch with non 02 absorbing and half with 02 absorbing and tried them periodically to see if it made any difference...
 
Posts #17 & 18 made the most sense not to sanitize the 02 caps for me. If you have an issue with not sanitizing them, then don't waste your money on them.
 
EyePeeA said:
Posts #17 & 18 made the most sense not to sanitize the 02 caps for me. If you have an issue with not sanitizing them, then don't waste your money on them.

But you don't lose the benefit if you sanitize them.
 
But you don't lose the benefit if you sanitize them.

According to Austinhomebrew, you do.

If you sanitize them you lose the oxygen absobing properties.

If you sanitize the O2 caps you lose the benefit and the extra money spent on the caps.

Additionally, both BierMuncher and Austinhombrew claim to have bottled hundreds of batches with unsanitized 02 caps and never had any infections doing so. That is good enough for me.

I suppose if you wanted to hedge your bets, you could create a slightly stronger sanitizing solution and dip the individual caps in quickly before bottling each individual bottle.
 
I have a pile of them waiting on the counter. Dunk in Star-San solution, load into my capper, and cap. The cap has less than 10 seconds before it's sealed onto the bottle. I know the chemical reaction can't be that fast. I don't know if the low pH of the Star San solution (2-3) affects its O2 absorption, but I am assuming it will still work.

I don't invert the bottles, so there's no point in waiting 30 seconds. It will kill anything on the cap surface after being sealed to the bottle. Again, the benefit of these caps may be marginal, but I generally use them on my bigger beers that I age for more than a year. After all of the time invested in these brews, it's worth a few extra cents to possibly preserve their condition.
 
According to Austinhomebrew, you do.

The caps use an oxidizing iron compound to sequester a small amount of oxygen from the headspace. The reaction happens over the course of days and weeks, not minutes or seconds.

I encourage you to do whatever makes you happy. There are all manner of things people elect not to sanitize, frequently without problems. A friend of mine has never used anything but water to clean his fermentor, and he sees no reason to change his practices. That's fine. But, it's simply incorrect to say that wetting the caps nullifies their effect (assuming they have any in the first place).
 
I agree that there are more than a few working methods which are practiced by successful brewers. But when it boils down to it, we don't really "know" how long it takes for the reaction to occur, or even how long we should dip our caps in sanitizer solution to effectively sanitize them, or if sanitizing caps even matters since you are now dealing with alcohol as opposed to a sugary wort. I've seen suggestions of immediately to 30 seconds to several minutes, and now you are saying days or weeks. It is really all just a crap shoot.
 
I agree that there are more than a few working methods which are practiced by successful brewers. But when it boils down to it, we don't really "know" how long it takes for the reaction to occur, or even how long we should dip our caps in sanitizer solution to effectively sanitize them, or if sanitizing caps even matters since you are now dealing with alcohol as opposed to a sugary wort. I've seen suggestions of immediately to 30 seconds to several minutes, and now you are saying days or weeks. It is really all just a crap shoot.

Not really. Iron salts react at known rates, which (at room temperatures) are far, far beyond the scope relevant for a normal capping process.
 
Jezus guys, this was all clarified in 2009.....I'v posted this a zillion times since then. That's the problem when folks necro posted in the oldest thread as opposed to the hundreds more recent ones.

revvy said:
Soaking them is what activates the oxygen absorbing magic. It actually takes a week for them to do their job on the bottle.

On Basic brewing James Spencer contacted the maker of Oxygen Absorbing Caps (Crown Beverage), and actually recommended you santize them quickly, evidently the "Oxygen Absorbing Effect" of the caps is not immediate and they need to be wet for a period of time before the magic happens, like days.

Click to listen

It's within the first few minutes of the podcast. Right after the opening and announcements.

They recommend sanitizing ONLY the caps you are using, and sanitizing just before bottling. But you do need to wet them, and it's probably the smartest idea to go and do it, with the sanitizer
 
Thanks for the further clarification guys. I joined HBT 5 months ago, so it's a good thing you posted about this again, Revvy.

Sanitizing ONLY the caps you are using definitely makes sense. You don't want to sanitize too many caps and then have to store them for later use, at which point they may be ineffective.
 
Case closed. Sanitize the caps and enjoy the benefits. The manufacturer confirmed that it takes days to complete it's work. This seems to be case closed.
 
Sorry to bring up old topics, but once you put the caps in sanitize do you need to turn the bottles over? if so how long should you leave them like that? Also do you sanitize them one at a time or all at once?

This is my second batch but first with the absorbing caps.
 
You don't have to store them upside down at all. It eats what O2 is in the headspace. But yes sanitize the caps first. They must be used within one hour after touching liquid. I usually throw about 20 in at a time so I limit my waste.
 
Old thread, new question. Will these affect the carb up in bottle conditioning? Don't we need some oxygen for that?
 
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