Should i aerate my wort

Oxidation of your wort can happen in several ways. The first is by splashing or aerating the wort while it is hot. Other beginning-brewing books advocate pouring the hot wort after the boil into cold water in the fermenter to cool it and add oxygen for the yeast. Unfortunately the wort may still be hot enough to oxidize when it picks up oxygen from the splashing. Pouring it down the side of the bucket to minimize splashing doesn't really help either since this increases the surface area of the wort exposed to the air.

In addition, if oxygen is introduced after primary fermentation has started, it may cause the yeast to produce more of the early fermentation byproducts, like diacetyl. However, some strains of yeast respond very well to "open" fermentations where the fermenter is open to the air without producing off-flavors. But even for those yeast strains, aeration or even exposure to oxygen after fermentation is complete can lead to staling of the beer. During racking to a secondary fermenter or to the bottling bucket, it is very important to prevent gurgling or splashing.

This seems to work well for me for aerating and mixing the yeast thoroughly with the wort. Especially for higher gravity beers and lagers, proper oxygenation is crucial for a clean and complete fermentation. Its also much more sanitary than splashing around your unfermented wort. Joe Sr. Official Poobah of No Life.

I have both the aquarium pump and the pure o2 system. I haven't done any controlled experiments to check the benefit of pure o2 but I prefer it. It's nice to have the aquarium pump as a back up, though. I wouldn't use a fuel filter. Why not just get the in-line hepa filter? I am not big fan of O2. I use venturi tube like this to airate the wort. I assume the threaded ends fit inline when draining wort from pot to fermenter but what do you attach to the barb to aerate with, bottled oxygen, an aquarium pump, what?

Yes the threaded ends are liquid in and out and barb end is the gas injection in. You could use O2 but I just use air with sterile filter. There are different sizes of venturi tubes. Oxygen is an important factor in several of these steps. With weak cell walls yeast have reduced membrane integrity resulting in; poor regulation of permeability, the inability to withstand higher levels of alcohol, and decreased cell reproductive health.

So oxygen, at least at this stage, is needed. It creates healthy yeast , and healthy yeast means better attenuation, more complete fermentations, lower fermentation times, less chance of a stuck fermentation, and fewer off flavors.

Oxygen solubility drops as the gravity of the wort increases. So, whatever your preferred method of aeration different methods are discussed below you will have to do it longer for both these reasons.

This will take some experimentation to find the length of time needed to get proper amounts of solubilized oxygen with a given aeration method, but a good place to start would be about twice as long as you aerate for an average batch of beer.

Also, if you are going to be doing lots of high gravity beer it may be worth investing in a few special pieces of brewing equipment designed to help with oxygenation.

You would want to do this before peak fermentation activity is complete and, as stated by White and Zainasheff, after the first cycle of yeast budding has taken place; about 12 hours into fermentation.

For average gravity beer there is some evidence that the simple process of preparing a yeast starter gives the yeast enough oxygen.

The process of creating a yeast starter includes agitating the mixture several times which introduces oxygen. A yeast starter kit can help you accomplish this. There is also data from an experiment you can read about here that suggests aeration via aquarium pump or agitation, plus leaving the starter unsealed to the air — in this case covered with tin foil — created the highest yeast cell counts.

As with all experiments, we have to remember that the biggest factor speaking to the quality and usefulness of an experiment is repeatable results. We have to define a couple terms here.

Most brewers consider any hot side aeration a bad thing. Hot side aeration can cause oxidation and lead to a beer going stale a lot sooner than anticipated. How much this hot side aeration actually affects the beer is up for debate, some brewers even consider it non-consequential.

Either way it seems a good idea to limit excessive splashing of hot wort. Why take the chance? Homebrewers usually use new yeast for every batch of beer, but some do harvest their yeast for reuse. If you are going to harvest yeast to pitch into another beer it is even more important that the yeast have the oxygen to reproduce, build healthy cell walls, and store nutrients.

You could say reused yeast is reliant on two different aerations, that of the beer it has come from and that of the beer it is going into next.

It is near impossible to not introduce some amount of oxygen during transfers. But this is nowhere near the volume needed for healthy yeast growth. As mentioned earlier, most yeast strains, at average pitching rates, into average gravity worts require close to the same range of oxygen. This range is 8 to 10 parts per million ppm. To get your wort into this saturation range you have a number of options. They are all relatively simple, but differ in their effectiveness and equipment needed. They include splashing, stirring, shaking, using an aquarium pump, or using pure oxygen.

The difference between aeration and oxygenation is a matter of quality. Aeration is the process of adding oxygen via the air, while oxygenation is the process of adding pure oxygen to the wort. Oxygenation on the other hand can give you substantially higher numbers. Wyeast labs published a chart that gives some idea of the effectiveness of the methods we will consider here. So use these as references only. This is easily done during the transfer to the fermenter.

You can secure your hose at the top of the fermenter so that the wort falls, splashing against the bottom. You can also create a spray at the end of the siphon hose.