Sterilise Crown Caps?

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barry.morgan71

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This may be a silly question but should you sterilise Crown Caps? I have done 2 brews so far and was just organising my Crown Caps before I start a 3rd and it suddenly struck me that everything else was sterilised but I didn't do the Crown Caps.
 
Yes, it's best practice, but if they are just out of the packet they should be fine.

Also, most crown caps now are oxygen scavenging, which needs to get wet to activate. So only sanitise as many as you need.
 
O.k. thanks, they were all just out of the packet, but who knows what the factory was like?
 
I don't think bacteria will thrive in the packet. I certainly wouldn't be concerned enough to recap all of my previous beer.
 
No I certainly wasn't thinking of doing that. The bottles I have drunk so far are o.k., it was just moving forward.
 
Yes, it's best practice, but if they are just out of the packet they should be fine.

Also, most crown caps now are oxygen scavenging, which needs to get wet to activate. So only sanitise as many as you need.
I'm glad you said this because I was going to sacrifice sanitising my caps on the basis that I was convinced you didn't want to get oxygen scavenging caps wet prior to capping for some reason.
 
Sanitisation is all about reducing the risk of nasties spoiling your beer. At the bottling stage, the risk is already far lower than at the start of fermentation (much lower sugar, and the alcohol content kills a lot of things (the reason beer was created in the first place!)).

There is a chance whatever small amount of bugs on the caps can spoil your beer if they get into it. I bottled for years without worrying and never had a problem (the beer doesnt' even come into contact with the cap if you keep it upright). But I sanitise mine now because it's dead easy to just dump them in a small pot of starsan and not worry about any nasties getting into the beer. It won't cause any harm.
 
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Also, most crown caps now are oxygen scavenging, which needs to get wet to activate. So only sanitise as many as you need.
I didn't know this athumb.. . I knew that oxygen scavenging caps were available, but didn't realise most were already.
 
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I didn't know this athumb.. . I knew that oxygen scavenging caps were available, but didn't realise most were already.
I didn't know that either. Just crimp them in place and then invert the bottle for a second. It'll also make sure all the priming sugar is where it should be. I've never sanitised new crown corks and I've never had a bottle go off. I should think the scavenging function is rendered useless immediately the caps get wet so o washing them perhaps is not a good idea.
 
IIRC, wetting the caps just starts the process, which is slow over the course of a few hours/days. So sanitising them when you start to bottle is fine, but sanitising them more than a day before (IE, if you do too many) is bad. This is just from memory, so may be wrong
 
The crown caps which have the polymer oxygen absorbing lining cost a little more (or did when folk believed they worked) the bags are clearly marked Oxygen Absorbing, but they did absorb hop aromas. I think that is what led to there down fall within the brewing industry. The idea was to spray a mist of sanitiser over the caps before use or just put them straight on out of the packet.
Bit of a waste of time for home brewers unless ageing the beer for a long period. Plus they don't stop oxygen ingress into the bottle.
 
Yeah I'm not convinced they scavenge enough oxygen to make a meaningful difference. I got mine from the homebrew company. Think they were 100 for £2 or so.
I would recommend spending a little more on caps than just buying the cheapest ones though, the first set I bought went rusty.
 
I’ve got one of those whooshy Italian bottle washers, great fun though not convinced any better than by hand in a bucket! I drop the caps in the base of the washer, a tip from the forum, use no rinse sanitizer, and shake off any excess and cap. Agree probably small risk but after all the work and expense not worth taking.
 
I count out what I "usually " get from a batch plus a few more incase I drop any. I chuck these into my bottle wash then fish them out as I bottle. Any spares I remove and dry on kitchen paper then reuse next time.
 
I’ve never sanitised my caps and never had a problem. Do commercial brewers sanitise them?
I've often wondered about things like this in commercial breweries. And a lot of people on the internet will just state things as fact without any evidence, then other people take their statement and parrot it on until it becomes "a known fact".

My assumption is that the bottle and cap manufacturing process comes out of a clean (but not sterile) factory and that the number of bugs is low. They stay in this state as they are transported to the bottling plant, where they are used in a clean (again not sterile) environment (they don't sit in a homebrewer's shed for 6 months). I haven't seen any bottle sanitisation before bottling (but absense of evidence is not evidence of absence). I assume again that the level of bugs on the bottles/caps is sufficiently low that it doesn't impact the beer.

(As an aside, I also wonder whether commercial beer bottling plants package the beer into bottles/cans under CO2 or normal air)
 

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