Why are you getting infected?

[Greg.L]

It's a very interesting concept (albeit the wiki description says it is not followed by real gases as strictly as the definition), but it does make me wonder if practically, the O2 passing across the glad wrap would be filtered of airborne bugs somewhat? Because due to the partial pressure theory, by the end of a standard 2 week fermentation process the head space of the fermenter is a complete mix of CO2 and O2, surely most people using glad wrap lids would be finding oxidation occurs on the surface at the very least?

There is also the practicality argument for those needing to lift the fermenter to take a sample, in order to stop airlock water being sucked into the beer I'd need to remove the airlock, opening a hole allowing air travel far more easily than a glad wrap lid true?

It is true that glad wrap stops airborn bugs, that is its main purpose. However we can never achieve sterile brewing, there will often be some acetobacter and film yeast in your brew already. I am not saying glad wrap will always cause oxidation and infection, just that it makes problems more likely. Just as you can never keep all the germs out, you can never keep all the air out but you have to do your best and minimise air contact at every step. It is the same principle as sanitising, you are not aiming for total control, just minimising the risk.

 

[JDW81]

This is another trap for homebrewers, the "traditional open fermenter" fallacy. Go to any microbrewery in Australia, you will see the fermenters are full, closed up and well sealed. If they aren't, they will be in a while after their first few infections. KEEP THE AIR OUT.

What about White Rabbit? They use open fermenters and their beer is infection free to my palate.

 

[CosmicBertie]

Research 'Yorkshire Square'. Beer has been brewed this way for many, many years.

 

[wide eyed and legless]

On a lighter note regarding yeast infections, I have read of a american brewer, I think it was the head brewer from Rogue brewery keeps yeast in his beard. Now if this is the case and he decides to do a bit of "Muff Diving" will he give her a yeast infection or if she already has a yeast infection will it affect his yeast ?

 

[DJ_L3ThAL]

It is true that glad wrap stops airborn bugs, that is its main purpose. However we can never achieve sterile brewing, there will often be some acetobacter and film yeast in your brew already. I am not saying glad wrap will always cause oxidation and infection, just that it makes problems more likely. Just as you can never keep all the germs out, you can never keep all the air out but you have to do your best and minimise air contact at every step. It is the same principle as sanitising, you are not aiming for total control, just minimising the risk.

Apologies if I am missing something, but I fail to see how glad wrap has a detrimental impact on fermenting techniques versus a lid and airlock based on what you have just said and our previous discussion. If you never need to remove the airlock for the entire brew then sure I can see that potentially the glad wrap is providing less resistance to air ingress. But in the real world I am sure along with myself, most of us would need to remove the airlock to avoid the water being sucked into the brew when lifting the FV which allows more air ingress than just the glad wrap lid?

 

[spryzie]

You don't need an airlock.

I do use a lid of course - but no airlock.

If you don't work in a room full of sterile air, then you're just putting an airlock on a container with wort and air full of bacteria already.

The magic is the yeast you inoculate the wort with will dominate the environment if you pitch immediately and get fermentation occurring soon after.

 

[Greg.L]

I really don't see much point in saying some brewers use open fermenters. Either you accept that you should keep air out or you don't. I would regard keeping air out as well established "best practice" for home brewers (and commercial brewers). If you want to go down the path of glad wrap, no airlock , half full fermenter etc then you have decided to accept a certain level of risk, that's fine but I don't think you should advise others to go that path. In terms of a thread on infections, oxygen is the main cause of infections so I am offering advice on keeping oxygen out.

 

[mje1980]

So what about all the people who hit their wort with pure oxygen at pitching time?. Are they all risking infection?

 

[CosmicBertie]

Surely its not oxygen that causes the infection, but the bacteria that is carried around by air. Oxygen has to be present for bacteria to grow (thus the aerobic phase of yeast growth) and thats why people splash their wort, shake the fermenter or pump oxygen through it. Catalyst.

Anyway, I was under the impression that oxygen that you pass through the wort at pitching time comes from a filter source.

 

[Greg.L]

Surely its not oxygen that causes the infection, but the bacteria that is carried around by air. Oxygen has to be present for bacteria to grow (thus the aerobic phase of yeast growth) and thats why people splash their wort, shake the fermenter or pump oxygen through it. Catalyst.

Anyway, I was under the impression that oxygen that you pass through the wort at pitching time comes from a filter source.

As I said before, most of the spoilage bugs are aerobic. You see an infection growing on the surface because that is the interface where oxygen in the air and sugar in the wort are both available. If you see stuff growing on the surface it means there is oxygen present. No oxygen, no infection.
As for aerating before pitching, that isn't relevant. Yeast use oxygen initially but quickly change to anaerobic fermentation, having used up all the dissolved oxygen. This stuff is pretty basic brewing 101.

you can compare keeping out air to sanitising. No-one would advise using a dirty fermenter, but if you use a dirty fermenter you probably won't have any problems, chances are you could keep using a dirty fermenter for a while without getting an infection. But why would you, we all know it is better to use a clean fermenter?

Unlike dirt oxygen is colourless and odorless, necessary for life. But you don't want it getting near your beer, it can only cause problems. At a low level it may not cause problems, but beyond a certain level it is 100% certain to ruin your beer. Why take the chance?

 

[mje1980]

Relating back to my other post, if this is the case, why do so many uk and European breweries have no problem with open fermentations??. I know I love beers like Samuel smith etc, which are open fermented and taste great. A lot of uk breweries also "double drop", where 24 hours after pitching, dump the wort into another fermenting vessel, that quite clearly and obviously adds lots of air into the beer. Again, those beers are beautiful

 

[Dave70]

Doesn't the yeast producce

As I said before, most of the spoilage bugs are aerobic. You see an infection growing on the surface because that is the interface where oxygen in the air and sugar in the wort are both available. If you see stuff growing on the surface it means there is oxygen present. No oxygen, no infection.
As for aerating before pitching, that isn't relevant. Yeast use oxygen initially but quickly change to anaerobic fermentation, having used up all the dissolved oxygen. This stuff is pretty basic brewing 101.

you can compare keeping out air to sanitising. No-one would advise using a dirty fermenter, but if you use a dirty fermenter you probably won't have any problems, chances are you could keep using a dirty fermenter for a while without getting an infection. But why would you, we all know it is better to use a clean fermenter?

Unlike dirt oxygen is colourless and odorless, necessary for life. But you don't want it getting near your beer, it can only cause problems. At a low level it may not cause problems, but beyond a certain level it is 100% certain to ruin your beer. Why take the chance?

Wouldn't you assume because the yeast are basically farting CO2 and simultaneously providing a blanket over the wort while displacing air, that would be enough to prevent airborne infection?
Or is the poultry amount of O2 in the CO2 all the bugs need to thrive?

Maby we could lower the risk with a squirt of gas before screwing down the lid or snapping on the glad wrap?

 

[spryzie]

As for best practice for home brewers - I use a Coopers fermenter and it doesn't bother with airlocks.

 

[warra48]

Relating back to my other post, if this is the case, why do so many uk and European breweries have no problem with open fermentations??. I know I love beers like Samuel smith etc, which are open fermented and taste great. A lot of uk breweries also "double drop", where 24 hours after pitching, dump the wort into another fermenting vessel, that quite clearly and obviously adds lots of air into the beer. Again, those beers are beautiful

Those beers are beautiful, but they also pitch a truckload of healthy yeast, and get a fermentation kicking off quick smart.

I'm not convinced all of us homebrewers always pitch enough healthy yeast to kick off a good fermentation. You only need to look up all the posts etc about delays in fermentation kicking off and lack of gloops in airlocks etc to realise that.

I have had some infections and dumped some brews, but I know the reasons in my case, and it is down to brewer error. Provided your brewing environment and all your equipment is clean, you follow proper sanitation techniques, and pitch an adequate quantity of healthy yeast after good aeration, you are surely close to guaranteeing a successful brew.

 

[GalBrew]

Provided your brewing environment and all your equipment is clean, you follow proper sanitation techniques, and pitch an adequate quantity of healthy yeast, you are surely close to guaranteeing a successful brew.

That sounds far too much like good advice warra.......reported. :lol:

 

[SimoB]

The rising damp thing is interesting, Strobe hit me up today. I had a drip tray from my keg system that I hadnt cleaned in ages and it was pretty dam funky i must say./ Some moldy business going on. i reckon that shiz was getting into my business and resulting in some shitty beer.

Have brewed some winners recently though so no drama there

 

[Camo6]

My drip tray is between the ferment fridge and where I store my grain mill. If I leave it full of spillage for a week it gets some lovely films growing on top. Probably risking it and need a bigger shed but haven't had a batch infection in almost five years of brewing, touch wood. I reckon when I do get one it'll be the result of brewer error. Beer and beer making just don't mix but at the same time are so damn good together.
That being said there's some pretty experienced brewers on here, from whom I've gleaned a lot of information, that have suffered from persisting infections despite the thoroughness of their procedures. Goes to show there are some variables which you can't always account for outside of brewing in a vacuum.

 

[DJ_L3ThAL]

brewing in a vacuum.

Bulk buy on shed-sized vacuum chambers?!

 

[Greg.L]

Blaming a drip tray for your bad brews - I think you've seen too many episodes of "House".

 

[mje1980]

Blaming oxygen for a lot of people's infections. You've been watching too much..... Well **** I don't know what you've been watching too much of.