Silicone O-rings are useless...apparently!

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Ever drank a keg beer in a pub?
I can tell you that the spear that threads in and seals the keg has a lovely silicone O-ring on it.
If lager becomes oxidised after a week in a keg it's likely not the O-ring that's to blame.

For those that want to buy them anyway, I say go right ahead. And and did you know I have some magical life-extending Murgy Straight that makes you more attractive and makes your willy bigger for only £3.50 per bottle? Send me your money! :)

edit: Or maybe they're EPDM...? Send me your money anyway.
I was thinking the same thing Andy. It’s funny how some of my beers stay perfectly fine for a few months in kegs with no issues.
 
All the same old binary thinking, that any aspect of brewing will only return no change or ruined beer.

Ever drank a cask beer in a pub?

Yep. Every single pint of cask beer anyone has ever drunk has been oxidised to some degree.
 
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Food grade silicone lube. As a matter of maintenance after every 3 corny keg uses they are broken down and all orings are cleaned relubed and rebuilt. I would have ignored the above knowing my system is bullet bullet proof.
 
I don't have any black O-rings so I'm assuming all of my are silicone pink or white apart from one yellow on my latest kegland keg.

Other than assuming over a couple of months on my hoppy beers they aren't quite as hoppy as the first few weeks I have just putting down to a fact of aging.

Interesting that maltmiller and Brewkegtap only sell black replacement kits at the moment, so maybe this fact has been out there for a while.

So I agree that it is probably a bit of a marketing thing by Kegland for people to buy into their new Low 02 product, whilst owning up to the downsides of the silicone that they were pushing before .

If the original reasoning for the silicone over Nitrate was the better retention of shape and maintaining a good seal over time. If the new kegland yellow has the same longevity benefits as silicone and Low 02 properties as good as Nitrate or better then £10 is worth spending.

Most of my kegs finish around 2 months so if there is a chance that my hop forward beers can taste better until the end then marketing/science aside I'm in for a tenner.

Maybe we have all just got used tasting beers that don't taste as good as the day it leaves the brewery, advantage of being a homebrewer we can try and have better beer.
 
Further to my previous post when I say the beers loses some of the hop flavour(and I mean not massively) that is beers that have been in cornies for several months not a couple.
They are claiming it spoils beer a lot quicker which I think is a scare tactic from the marketing side to make you buy.
In my opinion whichever O rings you use most brewers will have drunk the beer well before any issues arise.
I was drinking two IPA's last night, one 7 weeks in the keg and another 9 weeks in the keg and no degradation there so not scientific but real world
 
Don't forget it's a £10 every 6 months, if I read the above correct. Might need to change them prior to 6 months depending on brew schedule.

Next they will be saying they are offering a subscription service to receive new ones automatically.

I have a mixture of black and pink, I don't get though a keg that quickly and never seen the difference between either kegs with pink or black rings.
 
Don't forget it's a £10 every 6 months, if I read the above correct. Might need to change them prior to 6 months depending on brew schedule.

Next they will be saying they are offering a subscription service to receive new ones automatically.

I have a mixture of black and pink, I don't get though a keg that quickly and never seen the difference between either kegs with pink or black rings.

It's the beer that has a 6 month shelf life, not the o-rings.
 
All this debate, I must be thick but please somebody explain to me how oxygen gets into a pressurised keg?
 
All this debate, I must be thick but please somebody explain to me how oxygen gets into a pressurised keg?
The oxygen molecules 'dissolve' into the silicon material itself, they then migrate through the material and 'evaporates' out of the material on the other side, into the keg. As the O2 molecules are so tiny they are unlikely to meet any CO2 ones coming the other way. So, internal pressure doesn't really have any affect on this, it is based on amount of O2 in atmosphere, the temperature and the surface area of the material exposed to the O2.
What wasn't really explained is why the O2 molecule migrates though the material, it has no driver to move in a certain direction, it could of course just go round and round in circles or evaporate back out the way it came in.
Additionally, the tests were not the same, one o-ring was tested with air under pressure in the test keg and the other was with a CO2/N2 mix. For the home brewer it would have been better for the inside of the keg to be pressurised to around 10-15psi with CO2 at a temperature of 7-10C to mimic the conditions most people store their kegs in.
 
Just like politicians results of any test can be manipulated depending on the agenda.
Smoke and mirrors to me as I have said before real world homebrewers do not generally get this issue in the time frames they are suggesting.
If you want people to part you from your hard earned money then fully believe it or look back at your previous brews and make your own decision.
I know it is not a expensive fix if it needs fixing at all but just another exaggerated brewing company hype to make you buy something you may not need
 
@stripeyjoe Sounds like the adverts for whitening toothpaste "Clinically proven" to whiten the teeth, which translates to, if you clean your teeth with our toothpaste for 8 hours a day then after 10 years a whitening can be detected by a ultraviolet wavelength by microscope under laboratory conditions.
 
All the same old binary thinking, that any aspect of brewing will only return no change or ruined beer.

Ever drank a cask beer in a pub?

Yep. Every single pint of cask beer anyone has ever drunk has been oxidised to some degree.
True and cask beer in a pub as to be drunk within 3 or 4 days before it's only good for the drain. I've sent many an off cask beer back over the years.

We're talking about molecular level of O2 contamination. even the most hoppy beer has some tolerance to exposure of air, with the CO2 being pressurised the number of CO2 molecules will outnumber the number of diffused O2 molecules many millions of times over and with every pint pulled you're replacing that headspace with pressurised CO2 thus diluting the O2 even further. So the science is the science but in the real world it has a negligible impact if any at all.
 
only good for the drain.

So the science is the science but in the real world it has a negligible impact if any at all.
Yes, like I said, same old binary thinking, that any aspect of brewing will only return no change or ruined beer, and only considered in isolation. 😂

Perhaps things become less negligible when storing an Imperial Stout for 6 months, as an example.

However, it was more a point regarding beers in keg not being oxidised, followed by examples of oxidation. Even more bewildering when most on here are trying to replicate beers typically served on cask, which is by nature oxidised, in keg.
 
What wasn't really explained is why the O2 molecule migrates though the material, it has no driver to move in a certain direction, it could of course just go round and round in circles or evaporate back out the way it came in.
Molecules vibrate. The hotter they are, the more they vibrate. As they bump into eachother, they knock other molecules in random directions. See Brownian motion.

Given there are no O2 molecules suspended within the material at the "start" but plenty on the outside, some molecules will randomly get pushed into the material.

As time goes on, some of the molecules will randomly go back out the way it came in (as you correctly guessed) and some will randomly go in circles, and others will randomly go through the seal and into the inside. Once on the inside of the keg, they will mix with the CO2 and have a much much smaller chance of randomly getting bounced back into the seal material.

So there is no driver forcing them in a particular direction, it's just that the random paths will allow a small proportion of the molecules on the outside of the seal to migrate through the seal to the inside, and via the same mechanic, a random proportion of the molecules on the inside of the seal to migrate to the outside. But because there is a high proportion of O2 molecules on the outside and a small amount on the inside, the overall effect is that of a net migration of O2 into the keg through the seal (and by the same mechanism, of CO2 to migrate the other way)
 

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