Where does the possibility of oxidation come from?

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Depending how much co2 you have in suspension when fermentation is finished you may get some foaming. Temperature the beer is at could be a factor and how much starsan you have left in your bottles.

Those who ferment under pressure have the advantage over those of us who don't!
 
Some people individually prime their bottles with sugar, full with beer and then shake to dissolve the sugar. Don't do this! Any shaking just causes more beer to be exposed to the small amount of oxygen in the bottle head space.
This also expand why some beer mails end up oxidised as they have been shaken up repeatedly in transit.

Splashing the beer into your keg/PB/bottles will introduce oxygen, sometimes enough to oxidise. Rack your beer through a tube or bottling wand directly to the bottom of the container without splashing or pouring down the side.

Foaming as mentioned does force out excess air.

If there's oxygen in the headspace of the bottle, it'll oxidise your beer whether you shake it or not.
 
Handy few pointers there, foam in the head space and not shaking, which I would have done.
Just wondering how to get it to foam if I’m not to splash though.

As a first time AG brewer I wouldn't worry about it. You'll still make beer and there's bigger things of concern.

Really the oxidation problem in bottles applies mostly to really hoppy beers - American Pale ales and IPAs. Most other styles you won't notice it.
 
I think I will go with the Camden tablet. I have ordered this from Malt Miller Tasty Table Beer | The Malt Miller
It is all a bit daunting, exiting though 😀
Oh it is exciting - it still gets me every time. Love it.

Mmmm yes, looking at the Tasty Table Beer recipe, that's a style with which you will indeed have to be careful with the Oxygen - but TBH I really wouldn't sweat it: whatever you brew I'm sure it will taste great.

Are you planning to boil in the bag, or mash in an insulated container?
Incidentally I know there is a lot of information out there (way too much information really) - but I'd recommend Greg Hugh's 'Home Brew Beer' (available from CAMRA's online shop) as a rich and reliable source of well proven, modern, recipes as well as very down-to-earth step by step instructions :-)
 
I've been brewing and bottling for over 5 years. There is always an air filled head space in my bottles and I have never suffered from oxidation.

You might be brewing styles that aren't as easily affected (worst affected are the really heavily dry hopped beers like American Pales and IPAs), or there might be something about your bottling technique I don't understand.

Equally, may I ask if you've compared your bottled beer to the same beer that has been kegged with no headspace or into a CO2 purged keg?

I can guarantee you that if there's oxygen in the headspace of a bottle it will go into your beer, causing some level of oxidation. Whether it's at a noticeable level is a different question.
 
Oh it is exciting - it still gets me every time. Love it.

Mmmm yes, looking at the Tasty Table Beer recipe, that's a style with which you will indeed have to be careful with the Oxygen - but TBH I really wouldn't sweat it: whatever you brew I'm sure it will taste great.

Are you planning to boil in the bag, or mash in an insulated container?
Incidentally I know there is a lot of information out there (way too much information really) - but I'd recommend Greg Hugh's 'Home Brew Beer' (available from CAMRA's online shop) as a rich and reliable source of well proven, modern, recipes as well as very down-to-earth step by step instructions :-)
I’ll be using a Brewzilla.
 
I hope I'll be forgiven to linking to one of my own posts on oxidation, how to minimise it using Vit C and that the oxygen in the headspace in a bottle is absorbed far faster than the yeast from priming can consume it.
https://www.thehomebrewforum.co.uk/...are-they-mutually-exclusive.90186/post-957950
Whether your beer 'suffers from oxidation' is very different to whether oxidation occurs. With headspace, O2 in the bottle will be absorbed and will react with any reductive materials in the beer. Whether those materials reach taste threshold and how many of them react is more the issue. For highly hopped beers the problem appears to be that a small amount of oxygen can trigger a cascade of multiple reactions before reaching a stable oxidised state, with taste and visual changes then appearing disproportionate to the small amount of oxygen available.

(It's ok I'm not going down another rabbit hole of science stuff 🤪)
 
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This oxidisation advice is from Charlie Papazian’s Home Brewer’s Companion. I’ve done this with pretty much all my beers since reading this and never had a problem with oxidisation (I batch prime and bottle condition all my brews).
 
Have you had success using ascorbic acid to avoid bottle oxidation?
I can't claim to have carried out any controlled experiments, but when used in my dry hopped beers I've not noted any oxidation in the beer served from the keg or from bottles. However, I've also been taking other steps to avoid oxidation. Given the fairly wide suitable dosing (2-10g) with the 10g based on the very worst case scenario, my approach so far has been to mix a teaspoon of Vit C powder with the dry hops before adding them. The thought being that the hops are the material that oxidises fastest. I did try the hop bag and magnet approach but as you may have read on my brew thread ... that didn't work so well for me 😦.

Anna
 
I have recently purchased a tapcooler counter pressure filler . I had previously been flushing bottles with co2 via a separate line and picnic tap and then filling off the tap with a DIY counter pressure filler..it worked ok but did cause foaming if I didn't turn the pressure down on the keg as without accurate bleed valve it was difficult to control the foam. It worked though and didn't have any issues with oxidation that were that noticeable.
My first batch of bottling a hoppy golden ale started with oxidation issues. Within a week of bottling I had feedback that bottles had changed colour
IMG_20210504_184815.jpg
IMG-20210515-WA0006.jpg

I completed similar purging practices that I did with my DIY set up the first time, and went further with increased levels of purging a second time but this hoppy golden ale still suffered with oxidation within a week. The keg is still fine after a month.
After reading the article below I will be embracing the foam. The tapcooler is a great bit of kit but I think without some foam at the end you are still letting O2 in when you remove the filler . I think I may bottle the last of the golden ale using this technique to see if it solves the issue.
https://www.morebeer.com/articles/Minimizing_Oxygen_Bottled_Beer
 
I have the 'Tasty Table Beer' on tap at the moment, it's turned out very acceptable 🍺🍺
My son rates it as the best brew I've produced so far.
Went as far as rating it on untappd 😂

I mixed plenty of air with it when transfering it into the fermenter for the yeast.
Was gentle when opening for dry hopping, minimal disturbance or splashing.
On completion I pressure transferred into a keg.
 

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You might be brewing styles that aren't as easily affected (worst affected are the really heavily dry hopped beers like American Pales and IPAs), or there might be something about your bottling technique I don't understand.

Equally, may I ask if you've compared your bottled beer to the same beer that has been kegged with no headspace or into a CO2 purged keg?

I can guarantee you that if there's oxygen in the headspace of a bottle it will go into your beer, causing some level of oxidation. Whether it's at a noticeable level is a different question.
I hope I'll be forgiven to linking to one of my own posts on oxidation, how to minimise it using Vit C and that the oxygen in the headspace in a bottle is absorbed far faster than the yeast from priming can consume it.
https://www.thehomebrewforum.co.uk/...are-they-mutually-exclusive.90186/post-957950
Whether your beer 'suffers from oxidation' is very different to whether oxidation occurs. With headspace, O2 in the bottle will be absorbed and will react with any reductive materials in the beer. Whether those materials reach taste threshold and how many of them react is more the issue. For highly hopped beers the problem appears to be that a small amount of oxygen can trigger a cascade of multiple reactions before reaching a stable oxidised state, with taste and visual changes then appearing disproportionate to the small amount of oxygen available.

(It's ok I'm not going down another rabbit hole of science stuff 🤪)
I think may be @DocAnna explains it. My beers don't have enough hops to "suffer" from oxidation, but that doesn't mean there is no oxidation.
 
You might be brewing styles that aren't as easily affected (worst affected are the really heavily dry hopped beers like American Pales and IPAs), or there might be something about your bottling technique I don't understand.

Equally, may I ask if you've compared your bottled beer to the same beer that has been kegged with no headspace or into a CO2 purged keg?

I can guarantee you that if there's oxygen in the headspace of a bottle it will go into your beer, causing some level of oxidation. Whether it's at a noticeable level is a different question.
It will but will take a couple of years, depends on the style oxidised notes are looked for in some beers to give that sherry like flavour. Not for me but, gives me a headache. As a home brewer beer treated right, don't store over 20C, condition at fermenting temperature and drink sooner than later.
 
I hope I'll be forgiven to linking to one of my own posts on oxidation, how to minimise it using Vit C and that the oxygen in the headspace in a bottle is absorbed far faster than the yeast from priming can consume it.
https://www.thehomebrewforum.co.uk/...are-they-mutually-exclusive.90186/post-957950
Whether your beer 'suffers from oxidation' is very different to whether oxidation occurs. With headspace, O2 in the bottle will be absorbed and will react with any reductive materials in the beer. Whether those materials reach taste threshold and how many of them react is more the issue. For highly hopped beers the problem appears to be that a small amount of oxygen can trigger a cascade of multiple reactions before reaching a stable oxidised state, with taste and visual changes then appearing disproportionate to the small amount of oxygen available.

(It's ok I'm not going down another rabbit hole of science stuff 🤪)
Hey @DocAnna , I have a few follow up questions and comments...

I read the post you linked to - if I've understood you're adding VitC/ascorbic acid at dry hop to avoid oxygen pickup, right? This isn't currently an issue for me as I'm dry hopping at yeast pitch and high krausen.

But can you outline what steps you're taking at bottling to avoid oxygen pickup? Are you also using VitC here? Do you batch prime?

I found a couple of interesting posts on homebrew talk:
The first broadly said don't cold crash to avoid oxygen suck back.
The second is a very long but interesting thread of experiments to purge the air from the headspace in the bottles - he found both a CO2 spray and cap on foam were both effective.

One additional idea I had is to add a small amount of bicarbonate of soda to the the top of each bottle to generate a little CO2 as it reacts with the acidic beer - only issue with this is it would raise the pH, though probably (hopefully) a negligible amount.

Cheers,

Matt 👍🍻
 
One thing to remember is once yeast goes into the anaerobic stage it does not need oxygen. Only a small amount of oxygen will be taken up by the yeast from the head space of the bottle. Breweries have been bottling for years without any problem it is only now when shipping is out of the breweries hands it becomes a problem. It is not a problem for home brewers who look after there beer at the correct temperatures.
 
I did an experiment recently comparing bottling methods from my keg. I used a very hoppy beer that should show up any signs of oxidation.

I bottled 3 bottles with counter pressure fillers, pressurising the bottles with CO2 first and capping on foam once filled.

Bottle 1 was glass, with a crown cap.
Bottle 2 was Coopers PET with a new cap.
Bottle 3 was Coopers PET with a new cap, where the bottle has been filled with liquid and flushed with CO2 before filling.

The bottles sat on a room temperature shelf for 2.5 weeks before being refrigeration for 3 days before sampling.

What I found was that bottle 1 was unaffected by bottling. It was pretty much the beer from the keg, although I couldn’t compare side by side as my keg kicked straight after bottling.

Bottles 2 and 3 we’re indistinguishable from each other. Given them on their own I wouldn’t have called them oxidised, as they were only a teeny tiny bit darker than bottle 1 (to the point that it wasn’t really apparent when photographed). The fresh fruit salad aroma I got from bottle 1 was also more of an overripe fruit salad aroma.

Bottle 1 is on the left here:

8532AB32-6D88-4FE2-8D8B-253DD2199DE8.jpeg


This is obviously far from conclusive, but it did show for me that for now at least I’m better off filling into crown capped glass bottles for now rather than PET to keep beer fresh. I believe that the oxygen absorbing liner in the crown cap is more effective than the one in the Coopers bottle lid, but there’s a few other things that could cause the difference too.
 
I did an experiment recently comparing bottling methods from my keg. I used a very hoppy beer that should show up any signs of oxidation.

I bottled 3 bottles with counter pressure fillers, pressurising the bottles with CO2 first and capping on foam once filled.

Bottle 1 was glass, with a crown cap.
Bottle 2 was Coopers PET with a new cap.
Bottle 3 was Coopers PET with a new cap, where the bottle has been filled with liquid and flushed with CO2 before filling.

The bottles sat on a room temperature shelf for 2.5 weeks before being refrigeration for 3 days before sampling.

What I found was that bottle 1 was unaffected by bottling. It was pretty much the beer from the keg, although I couldn’t compare side by side as my keg kicked straight after bottling.

Bottles 2 and 3 we’re indistinguishable from each other. Given them on their own I wouldn’t have called them oxidised, as they were only a teeny tiny bit darker than bottle 1 (to the point that it wasn’t really apparent when photographed). The fresh fruit salad aroma I got from bottle 1 was also more of an overripe fruit salad aroma.

Bottle 1 is on the left here:

View attachment 48161

This is obviously far from conclusive, but it did show for me that for now at least I’m better off filling into crown capped glass bottles for now rather than PET to keep beer fresh. I believe that the oxygen absorbing liner in the crown cap is more effective than the one in the Coopers bottle lid, but there’s a few other things that could cause the difference too.
And keep them at a lower temperature. The higher the temperature the more chance of oxidation. I keep all my bottled beer at around 17C lower in winter.
 
Hey @DocAnna , I have a few follow up questions and comments...

I read the post you linked to - if I've understood you're adding VitC/ascorbic acid at dry hop to avoid oxygen pickup, right? This isn't currently an issue for me as I'm dry hopping at yeast pitch and high krausen.

But can you outline what steps you're taking at bottling to avoid oxygen pickup? Are you also using VitC here? Do you batch prime?

I found a couple of interesting posts on homebrew talk:
The first broadly said don't cold crash to avoid oxygen suck back.
The second is a very long but interesting thread of experiments to purge the air from the headspace in the bottles - he found both a CO2 spray and cap on foam were both effective.

One additional idea I had is to add a small amount of bicarbonate of soda to the the top of each bottle to generate a little CO2 as it reacts with the acidic beer - only issue with this is it would raise the pH, though probably (hopefully) a negligible amount.

Cheers,

Matt 👍🍻
Sorry a wee bit slow on the replies today - busy day picking my son up from University.

Ok the ascorbic acid is an oxygen scavenger - or to be picky - it scavengers oxygen free radicals which isn't quite the same as dissolved oxygen but is the active oxygen that causes oxidation. Ascorbic acid isn't stable to heat so there's no point adding while the wort's boiling.

I add vit C at the dry hop stage, and it doesn't matter if you are dry hopping at high krausen, the process of dry hopping will inevitably introduce oxygen unless using pellets in a bag which was introduced at the start of the ferment (the magnet release method). Cold crash doesn't have to introduce oxygen if you use a balloon filled with CO2 - How to: Balloon CO2 collection (Bruloonlock)

The experiments on the amount of air in a bottle are v interesting, essentially cap on foam seems to be the key part. If you've cold crashed and carbonated before bottling then it's a bit easier, more problematic if bottle conditioning. I'm not sure about the bicarb method, I suspect the amount of bicarb needed to generate enough CO2 would also alter the flavour.

I've had vague wonderings about how it might be possible to fill the bottles in a covered environment so that removing the filler sucks CO2 back rather than air. At the moment when I withdraw the filler I have been squirting CO2 in the neck which causes enough turbulance in the liquid to generate foam to cap on.

Anna
 
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