Oxidisation In Homebrew Beer Easy Guide

It is a point of fact that many homebrewers are oxidising their beers without realising it because they drink them before the full onset of staleness takes hold.
Much better tasting beers can be enjoyed from the start by using techniques that either reduce or fully remove oxygen.
This video looks at this effect and presents solutions for all, which I hope prove useful for the community.

Channel links:-

Introduction music:- Drink Beer (Till The Day That I Die) by Dazie Mae

[ShortCircuitedBrewers]

Great topic David! I have been a proponent of low oxygen transfers to keg for a while now. The only thing people have to understand with my video that you linked to is that it does take a while to allow gravity to do the work in the closed loop transfer. It is a small price to pay, in my opinion, for beer that lasts much longer if you do it that way. Cheers and thanks for the shout out!! 👍🍻

[richardeldridge]

Wow, thank you. That's probably why my cream ale turned brown in my keg after a month. The hose shot out of my keg and spilled beer everywhere when using the auto siphon on this batch. I'm still learning but having fun.

[niznikb]

Great video as always! What I found especially interesting (and confusing, at first) is the test you show at 1:33.
I was familiar with this method as an aid to detecting "metallic off-flavor" in beer but never heard or read anyone mentioning that the "metallic smell" can also be a sign of oxidation. It seems that the general opinion is that the smell indicates the presence of metal ions (usually iron or copper), which means you have too much iron in your brew water or a faulty brewing equipment (like chipped enamel in your pot).
Then it struck me: A few months ago I watched a video on NileRed channel titled: "You can't smell metal". It explains that what we perceive as "metallic smell" is actually caused by some decomposition products of our sweat and body oils to which metal ions act as a catalyst. We assume that what we smell is "metallic" because we associate the smell with handling metal with our hands.
Here's why I think it's important:
It turns out that the compound most responsible for the "metallic smell" is a ketone called 1-octen-3-one and what's especially interesting is that our sense of smell is extremely sensitive to it, so it's detectable even in tiny concentrations (a few ppt). It is a product of oxidation of 1-octen-3-ol (octenol).
Octenol is in turn formed during oxidative breakdown of linoleic acid, which is the most abundant fatty acid found in cereals (barley and wheat included). Octenol (also known as mushroom alcohol) itself is one of the causes of a wine fault known as "cork taint" and similar off-flavors (like moldy newspaper or a damp basement) can be found in beer that was improperly stored.
It thus makes sense to me that among the multitude of chemical reactions that take place in aging beer, the oxidation of linoleic acid -> octenol (musty, mushroomy) -> 1-octen-3-one (metallic) is one that might explain why the "metallic smell" might be absent in fresh beer, but start to appear after some time if the beer was oxidized.

[oldschoolman]

Just purchased a snub nose pressure fermenter with a 2.0 spunding value and will be doing closed transfer and co2 purge when bottling. I also want to try and capture the co2 generated during fermentation to push sanitizer out of the keg before filling. Happy brewing and cheers!

[BobHerres]

Excellent video! Tons of great information. Thank you for sharing this.

[fdk]

Nice video! Could you elaborate a bit about hot side aeration, what it is, why it's an issue in commercial brewing and why it's not an issue in homebrewing?

[richardcampbell]

Great video David. It would have been useful to know what to do the the chemicals you suggested so I could trial their use.

[paulrobertson]

More food for thought. Thank you David :)

[boris]

From my experience as industrial QC worker, kegs are best for low oxygen exposure.
But if you are bottling at home, and have no counter pressure bottle filler, or access to CO2, to avoid oxygen, when filling the bottle, as you probably already know, always fill it from bottom, and let it foam out a little. This will eliminate some of head space oxygen, which is over long period worst for shelf life of beer.
There are also special crown corks which have so-called oxygen scavenger material instead of normal silicon plastic, this material collects oxygen left in head space of the bottle.
Industrial filler actually use a device called HD, it hits filled beer with a strong narrow jet of sterile water second before crowning, it foams the beer out a little, which is good because it also removes some oxygen from beer as CO2 bubbles carry oxygen out with them.
Maybe you could emulate this at home with medical syringe with needle filled with hot sterile water, but i personally have not tried this, and it would probably make a mess...

[jakubmarciniec]

Hello David, thanks for the video! Do you think rinsing glass bottles with sodium percarbonate sanitizer before filling can cause oxidization of beer, too?

[fdk]

Also, what's your opinion on the low oxygen brewing trend going on in homebrewing circles? It seems unnecessarily complex to me.

[mikemotta]

Thanks David, very informational. I still do a good amount of bottling and the caps that i use are sold as oxygen-absorbing, designed to eliminate any oxygen left in the head space of the bottle. Do you have an opinion on the effectiveness of these bottle caps?

[rickhanover]

Great video but in my opinion sodium meta-bisulphite should be regarded as a potentially hazardous substance, and I personally stay well away from it when brewing. SMB can trigger asthmatic attacks in asthmatics, (due to the release of sulphur dioxide from solution, (in this case your beer) and is also regarded as being an irritant at quite low concentration. It can also affect taste parameters. Many food processors avoid its use as a preservative these days, using sorbic acid instead or other alternatives

[andrewsayers]

Thanks for this David I've been brewing my first all grains in the lower abv range around 3.8 to 4.0% are you aware of any evidence this would stale quicker than say higher abv, does the alchohol act as say preservative? Thanks

[TheRscorp]

Wouldn't you only be able to use potassium metabisulfite if you're carbonating by blasting in CO2 in a keg? I make wine and mead and use it, but those are for still wines when no carbonation is desired. If I make a priming solution and then bottle, wouldn't the potassium metabisulfite inhibit the fermentation in the bottle and ruin carbonation?

[Heybat]

Bottle conditioning allows for longer shelf life of the beer in this regard. The yeast inside the bottle consumes all of the oxygen very quickly.

[mrtwdjh]

so lets say i have a carboy with the size 10 gallon, and i only want to brew 6 gallon, will the 4 gallon space at the top during fermentation, will it oxidise my beer? provided that i am not going to open it till the day i bottle

[trevormasters]

Do you purge the keg *before* you put the beer in?

[DENIEL]

My beers go wrong in keg, after like 10 days after kegging. It doesn't smell metallic, more like bread smell and bread off flavour, or I just ate breads that taste like cardboard idk...it's hard for me to recognise. I did not have this issue when I bottled my beers. Next time I brew, I will put half of the beer in the keg, and half in a brand new 5 l keg wich will be carbonized with co2 cartridge. So I can tell if my corny keg or my co2 is bad. Or I just do sg bad during the brewing part. I use fermzilla, ferminator and tilt while fermenting, so I think that part is okay.

[johncspine]

I’ve been away from homebrewing, have neck hardware that makes heavy lifting difficult..a transfer pump to get wort to the boil would solve problems, but..the old books (Fix..Oktoberfest) I have say “rough treatment..turbulent transfers..affect quality.” Opinion? It would help me out!