ImperialStout

Recipes 

I brew big beers, usually 18 to 23 pounds grain and 8 to 10% ABV using dry yeast only. Have been reading about aerating big beer wort to give the yeast enough oxygen but does this apply to dry yeast?


From the Danstar FAQ:
Quote:
I always aerate my wort when using liquid yeast. Do I need to aerate the wort before pitching dry yeast?
No, there is no need to aerate the wort but it does not harm the yeast either. During its aerobic production, dry yeast accumulates sufficient amounts of unsaturated fatty acids and sterols to produce enough biomass in the first stage of fermentation. The only reason to aerate the wort when using wet yeast is to provide the yeast with oxygen so that it can produce sterols and unsaturated fatty acids which are important parts of the cell membrane and therefore essential for biomass production.

If the slurry from dry yeast fermentation is re-pitched from one batch of beer to another, the wort has to be aerated as with any liquid yeast.

Does the above apply to big beers or is it better to aerate? I typically hold drain tube from cooled wort in brew pot well above the wort level in the fermenting bucket. Is further aerating necessary for big beers? If so, how to aerate? An aquarium pump for a 5 gal tank and a small stone cost $10. Devises that use oxygen cylinders are faster and provide more oxygen but they cost $40 and more. If you aerate what do you use. Can a small fuel filter be used to trap impurities from the air?

__________________
"Ask not what your country can brew for you ; ask what you can brew for your country."

"ich braute dieses Bier mit meinem Hund" (Life is indeed short: Get a Beagle and a Beer

Ondori

Recipes 

I have heard on brewstrong that using an o2 tank with a difuser stone works amazingly well. I have yet to try this yet though.

latium

Recipes 

Wyeast has an article on their site about oxygenation: http://www.wyeastlab.com/hb_oxygenation.cfm

Even though it might not be strictly *necessary* with dry yeast, it's a good habit to get into. From my reading of the article, it might be a good idea to let a little kettle trub get into the fermenter if you're not using pure O2.

Another interesting idea that New Belgium has tried is using olive oil in place of aeration:
http://www.homebrewtalk.com/f13/using-olive-oil-instead-oxygen-47872/
http://www.brewcrazy.com/hull-olive-oil-thesis.pdf

Edited to add: As far as how I do it, I got the kit from William's Brewing which puts the stone on the end of a metal tube. I figured that way, I could be sure the O2 bubbles would have maximum contact time with the wort before reaching the top. I'm thinking about getting another stone, though (just the stone) for aerating starters. I didn't think that was too necessary with a stir plate, but I'm not sure.

SagamoreAle

Recipes 

I typically hold drain tube from cooled wort in brew pot well above the wort level in the fermenting bucket.
--> You're probably getting plenty of aeration at that point
--> If you want more aeration, put a screened funnel into the carboy and empty your drain tube through it
--> If you want to take it further, get a Siphon Spray Wort Aerator for $4 from your fave LHBS (this is what I use)

I use an aquarium pump with an inline filter for my yeast starters.

Hard to tell if you're considering aerating your wort after pitching the yeast. I'd avoid this because at some point you are just oxidizing your brew.

I always make a starter and aerate the wort prior to pitching, regardless of whether or not I use dry or liquid yeast. I think it's a better practice.

__________________
Ex fermentum, scientia.

nsrooen

Recipes 

From the research I have done and have been using.

.5 micron stone for pure oxygen. Smaller bubbles dissolve easier in your wort. You do not want the oxygen bubble to reach the top of your wort. You want them to dissipate within the wort before they reach the top.

I do 1 ppm for 1 minute per the Yeast book recommendation by Chris White. Not sure what the optimal setting would be for a 2 micron stone.

Oxygen Welding Tank -
http://www.harborfreight.com/20-cubic-ft-oxygen-cylinder-92810.html
Get an empty from Harbor Freight with 20% off coupon and exchange it at a gas supply place for a full one. Supposedly medical tanks and welding tanks are filled exactly the same way from the same source, one is just is "certified". Bigger upfront investment but you wont have to constantly mess with getting the small ones at the home improvement stores, The 20 cubic tank will last you a long, long time.

Add this -
http://www.amazon.com/Oxygen-Regulator-CGA540-colored-protector/dp/B00697ZYTA/ref=sr_1_fkmr1_2?ie=UTF8&qid=1359497160&sr=8-2-fkmr1&keywords=cga+oxygen+meter+1-4
Whatever you get needs a CGA450 connection for the tank. It is great to be able to precisely control the flow of oxygen.

and a stainless steel oxygen wand and you are set. The wand allows you to quickly / easily position the stone at the bottom of your fermenter.

I did a fair amount of research before I decided on this route and so far I have had excellent results.

If you decide to go aquarium pump route - get the 2 micron stone and a inline Hepa filter. Most of the big online retailers carry them.

Cyclman

Recipes 

Yeast need oxygen. Especially with high OG wort, atmospheric aeration in inadequate. Buy an oxygenation stone, pitch adequate yeast, your beer will dramatically improve. One of the best beer making investments.

ApothecaryBrewing

Recipes 

This from William's brewing!

I was having stuck fermentations that would hang up around 1.020. Got this thing for christmas and haven't had a stuck fermentation since. Liquid or Dry, proper aeration makes a world of difference in process and product!

An aquarium pump with a filter and air stone on it would work but you would only be getting a maximum of 8ppm dissolved oxygen since that is the most the atmosphere can provide. By using pure oxygen, you are able to hit the recommended 12-15ppm dissolved oxygen content in your wort. Thats why I went with the o2 kit.

Spend $40 for an aquarium pump, tubing, stone and filter or cough up a little extra for pure o2 and never worry about contamination or under-aerating.

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Brewpothecary

SagamoreAle

Recipes 

Nice piece of equipment; hits my equipment junkie button. I think I have an aeration problem I need to solve...

__________________
Ex fermentum, scientia.

MMJfan

Recipes 

I use a graut mixer attached to my drill for aerating my worts and that works fine for me...

slyk9

Recipes 

Disposable oxygen canisters from Lowes or HD go for around $7. I use a regulator from Williams (best price I've found) and a SS stone from my LHBS. No HEPA filter and no problem with infection provided you sanitize everything and boil the stone to clean it. I get around 6 batches per tank. There was a big improvement in my finished product.