12

It seems that it was used at New Belgium primarily for yeast storage between brews, not fermentation. AFAIK, New Belgium stopped doing it after a short trial (one batch of Fat Tire) when they found it led to premature staling and off flavors. I know of only one controlled test of it on the homebrew level and the tasters in a blind triangle tasting ...


9

To quote from http://www.wyeastlab.com/hb_oxygenation.cfm: It was concluded that pumping compressed air through a stone is not an efficient way to provide adequate levels of DO. Traditional splashing and shaking, although laborious, is fairly efficient at dissolving up to 8 ppm oxygen. To increase levels of oxygen, the carboy headspace can be purged with ...


5

It's very much temperature dependent. In an episode of brewstrong, Charlie Bamforth mentions that the rate of oxidization is proportional to temperature, and increases 3 fold for each temperature increase of 10°C/18°F. So, if your beer is stored at 4°C (39°F), it will oxidize 9 times slower than if it's stored at 24°C (75°F). Loosely speaking, if it takes ...


4

How would you describe the off flavor? Most likely scenario is that the beer picked up an infection somewhere between primary and the keg. Maybe you've got something funky growing in your lagering fridge? In the jumper hose? The keg itself? I'd suggest replacing all the beer line, and sanitizing anything you get bleach on.


4

I pour my wort into a bottling bucket and then letting it freefall from the spigot into the fermenting bucket about 2 feet below it. It's easy and it works well for me. I put aeration on the "art" side of brewing as opposed to the "science" side b/c I have no idea how to calculate O2 parts per million in my beer... Also, I watched my buddy "shake" his ...


4

Oxygenating your wort using a tank is leaps and bounds more efficient (as well as more expensive) than agitation or splashing. Simply agitating or splashing your wort to oxygenate it will work for most average gravity beers (you're aiming for a minimum of eight parts per million of oxygen minimum), but will otherwise require a significant amount of effort ...


4

Any way you take a sample (unless it's from a pressurized vessel with an outlet) will draw air in. As you suspect, it should be a small amount, and given that your beer A) may still be fermenting (which CO2 will help strip any introduced oxygen out of the beer) and B) definitely still has yeast in it (which will scavenge oxygen, as long as it's still alive), ...


4

You've already understood the general practice. Air (really oxygen) is needed in the wort prior to pitching so the yeast can grow and replicate. After pitching, a sealed environment is desired. I think the reason its OK to aerate with air (vs, say, pure O2) is that the yeast, if healthy, will usually overwhelm anything else trying grow in the fresh wort. ...


4

I would oxygenate (pure O2) right before or after the pitch. Just because the process has the chance to introduce bacteria or wild yeast and it's best if the yeast is there to become dominate before anything else. Aeration has much less risk, if just splashing or shaking the wort. I don't think this would matter much when it's done.


3

You are confusing a couple of things. You want oxygen for a robust fermentation, no doubt about that. BUT, after the primary fermentation is done, you want to cut off the supply of oxygen otherwise the mead/wine/beer will oxidize because there is nothing to consume the oxygen. With beer we replace that with CO2, but with mead and wine you need to do ...


3

I wouldn't think of these things necessarily food safe. I wouldn't be adding something like this to my beer/mead without knowing what other substances are in it. You are overthinking the oxygenation/aeration process. Aside from using a small O2 tank and stone; people are making excellent mead by simply agitating the must during transfer and/or shaking the ...


3

Yes, it definitely should be a feasible method. Yeast will rapidly (within a matter of hours) consume the oxygen that has been provided, at which point you may provide it more and it will happily accept. The important point in determining the quality of the subsequent fermentation, as you suggest, should be how much oxygen the yeast consumes in total. ...


3

Generally green apple (acetaldehyde) is due to fermentation not being complete. Did you cold crash? Did you verify that your beer was done fermenting? It is strange that your fermenter builds up so much pressure, even with an airlock attached. Are you filling the airlock to the top or to the line? Too much CO2 will cause the yeast to slow down, which ...


3

I will start by assuming you have an pure O2 tank, regulator, and wand/diffusion stone setup. Because it is impossible for you to over-oxygenate your wort by any method that uses air rather than pure O2. I don't think there is a scientific consensus on how much oxygen is too much, and even measuring oxygen levels is a tricky business. I think there is ...


3

People have used olive oil with some success, see some conversations here or here. The general consensus is that it works, but most seem to agree that there isn't much point of doing it on the pico scale unless you like to experiment.


2

I think Tobias is correct. It sounds like you've picked up some wild yeast or bacteria from somewhere. You need to clean everything that beer touches after boiling. I recommend: Replace all of your tubing. Disassemble and soak everything (that is plastic or stainless, including all of the new tubing) overnight in hot water and PBW or Oxiclean. ...


2

Too much oxygen in a starter is almost impossible, so long as you decant the liquid and don't pitch it with the yeast. If you plan to pitch the liquid (e.g. to kraeusen a beer or restart a stuck ferment) then don't stir at all since you'll be pitching oxidized wort. A vortex isn't necessary for oxygen uptake - just having the surface in continual motion ...


2

My experience as as professional brewer and home brewer leads me to suggest that oxygen is not detrimental to beer flavor unless yeast activity is in decline (i.e., after vigorous fermentation has subsided). So if you have forgotten to oxygenate, go ahead and do so as long as your beer has yet to achieve high krausen.


2

The yeast need the oxygen to grow and reproduce, which is important for the first stage of primary fermentation when the yeast is multiplying and inhabiting your wort, which you want to happen as quickly as possible to avoid risk of infection when the wort is cool, exposed to air and does not yet have a protective yeast head. Unless you're brewing a high ...


2

Once fermentation has started it is usually not recommended to add oxygen. Exceptions: When brewing a high alcohol beer you may add oxygen up to 12 hours after pitching, but not afterwords. Yeast will consume oxygen during the initial fermentation phase. After that the oxygen stays around to stale your beer.


2

The other solution is to pitch enough yeast to make aeration unneeded or at least less necessary. That's what I do.


1

The basics: just mix it up. I've made a few 5-gallon batches of mead, 30-some by this point. When mixing together my must at the start of a batch, I used to use just a big steel spoon to stir the heck out of the must and make sure I worked in a lot of air and got things nice and frothy. Nowadays I use a regular immersion blender, which has the added ...


1

Well, first of all, the grain bill is not one of red flanders. There's no place for chocolate malt, nor for flaked corn. 8 kg base malt is gonna give you too high OG for the style (assuming you're doing 5gal/20l batch). Too much hops, too (again, assuming 20l batch, but too much even for 40l). The share of special malt of caramel-ish type should be much ...


1

I think the aeration method outlined would work by making a lower but more prolonged level of O2 available - but it might be over elaborate or even unnecessary. The need for oxygen during fermentation is not continuous. As noted, the yeast only needs it to grow. It is not needed to metabolise sugar to alcohol/CO2. So once the required yeast population is ...


1

I took the attachment back to the homebrew store and they replaced it and attached trhe replacement themselves. Since then I have used the bottle for several batches. I guess it was a defective gasket.


1

The factors determining oxygenation are yeast health vs taste of the beer. Ever tasted a starter culture, or a bottle that was only bottled a couple days ago? They will be full of acetaldehyde, the cidery/green apple flavor of oxidized beer. It is correct that the yeast needs some oxygen for replication and general healthy-ness, but at the end of the ...


1

Hot, fusel alcohol flavors generally correlate to stress in the yeast — insufficient population, not enough nutrients, or insufficient oxygen levels in your starting wort. If you're getting these off flavors for even a smaller beer at 1.050, in the very least do the following: in your boil, add yeast nutrients in the last 15 minutes of the boil, and ...


1

Aerobic is for propagation, anaerobic converts sugar into alcohol and carbon dioxide. I doubt a small amount would hurt, like from transfer or minor splashing, but if you intentionally injected oxygen, like how you might aerate the wort prior to fermentation, I would imagine it would not carbonate well and produce a lot of yeast, giving it a "yeasty" ...


1

I recently started using O2 and temperature control, as well as turning my attention to brewing big beers (SG 1.100+). These big beers have come out clean, attenuated well, and were generally much better than previous attempts to brew even moderate beers around SG 1.070.


1

I used to use one, but I found it a hassle to use compared to my MixStir aerator. In addition, I found the Mixstir to work as well as any other method and it's considerably less expensive.


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