Originally By Tony Ackland
Oxygen requirements for FermentationDuring fermentation, yeast has a couple of choices. If it has oxygen available to it, it will be able to reproduce quite rapidly (doubling every 3 hours). If there is only limited oxygen available, it will turn its task to producing ethanol and other products (about 1300 in all), like higher alcohols (sometimes called fusel oils), esters, organic acids, and carbonyl compounds. To get good initial growth of the yeasts, you want to have a bit of oxygen available - but you can do this simply by stirring the wash vigorously when disolving the sugar. Once you have added the yeast, it is critical to seal the container such that air cant get in, but you can still let the CO2 out, by using an airlock. To minimise the amount of other volitiles produced, make sure that you are using a yeast designed for the job, and keeping it happy with nutrients & with a stable temperature.
Fizz writes ..
2.) I would recommend using a racking cane with a small piece of tubing connected to your air stone. Let me try to explain better: You have you air pump connected to the correct length of tubing to get to your wash. You connect that tubing to your racking cane. To the other end of the raking cane you add a small piece of tubing, and to that tubing you put on your air stone. Then you submerge the air stone by placing the raking cane into the wash. What this will do for you is allow you to position the air stone where ever you may need to, but more importantly it will keep the stone from floating to the top of the wash. By using the raking cane (or similar device) method you now have more control over the air stone while making sure that it remains submerged.
There are brew shops that sell both of these products. Some even sell special "air wands" that come with both the filter and a special "wand" that keeps the air stone submerged.
If you would like more information, or at least a look at some products for this topic, I would recommend going to http://www.williamsbrewing.com/. Go to the fermenting equipment section and then go to "Wort Aeration" section to look at some products that deal with this issue.
So how do you put O2 in your wash?