Aeration

[S.F.B.]

Reading another thread, I got to thinking about lag time before the fermentation starts. One of the ways to get it going quickly is to use a good starter. A good thing to do to help the starter get things going is to make sure your wort is well aerated. For the most part, the splashing of the wort into the fermenter is enough to adequately aerate it. I like to take it another step further. I use an aquarium pump to get that extra bit of oxygen into the wort before I pitch the yeast. Since starting this, I have not had a lag time of more than 10-12 hours.

Does anyone else do this or have another method of aeration? I know there are more efficient ways but this is the most cost effective I know of.

Just a little FYI for those who may be interested.

[paul84043]

I use the oxygen injection through the 2 micron air stone. Can't think of a better way than that.
I have seen some numbers on this system, it supposedly puts as much oxygen into the wort in 1 minute, as you could get in with a full hour of aeration with an air pump.
It might be selling hype, but I can't see it hurting at all.

That said...I have had 2 batches with a pretty serious lag time. Both times the yeast did not have the prescribed amount of time to "Start"....my bad...

[Tweek]

I use a yeast starter and an o2 stone, plus I use the spigot on my brew pot which is elevated with a piece of food grade line on it to transfer into my carboys. This comes out quite fast and is pretty much suffiecient in itself. Since I have been using this method I rarely get a lag time of more than 4 hours.


edit- I make 10 gallon batches so I make my starter around 5 or 6 pints the day before and split it between 2 carboys (and a little back in the vial for next time). This really lets the yeast hit the ground running.

[quantum24]

what are these o2 stones you guys are talking about? and if they are any good, where can you get them ( ive never seen anything like this at my local hombrew store)

[b3s]

Originally posted by quantum24
what are these o2 stones you guys are talking about? and if they are any good, where can you get them ( ive never seen anything like this at my local hombrew store)

http://www.stpats.com/diffuser.htm

[paul84043]

They are available at pretty much any of the online brew stores, (example.. http://www.annapolishomebrew.com/shopping/coolstuff/index.asp )they are actually scintered stainless steel. You have to order the stone, the tubing and the regulator unless you already have one. I would keep one just for this setup, I'd hate to put some other strange gas into your wort....
A inline filter is optional, I haven't convinced myself yet that I need one of those.

They typically run 30$ or so, and the O2 canister you can pick up at a hardware store.

They're easy to keep clean, I just boil mine for a few minutes when I'm pre boiling water.

[fuji6100]

I use a large stainless steel (sterilized) whisk and whisk vigorously for a minute or two. I also hydrate my yeast 30-45 minutes ahead of time and get them started in 2 cups of cooled wort before adding to the aerated solution.

My bubbling usually begins rapidly, in only 8 hours the last time (at 74 degrees)

[shughes600]

Originally posted by paul84043
I use the oxygen injection through the 2 micron air stone. Can't think of a better way than that.
I have seen some numbers on this system, it supposedly puts as much oxygen into the wort in 1 minute, as you could get in with a full hour of aeration with an air pump.
It might be selling hype, but I can't see it hurting at all.

That said...I have had 2 batches with a pretty serious lag time. Both times the yeast did not have the prescribed amount of time to "Start"....my bad...

There is no hype there. Atmospheric O2 is 21% at best, whereas your tank is >99% O2.

Poor starts might be due to OVER aeration. O2 in nearly pure quantities will kill your yeast. I can't remember where I saw it (maybe BYO) but pure O2 is recommended for <5 minutes every hour for a few hours (4 to 24). I can't remember the details of the routine just that pure O2 in excess quantities will kill your yeast.

[shughes600]

Originally posted by paul84043
A inline filter is optional, I haven't convinced myself yet that I need one of those.

They typically run 30$ or so, and the O2 canister you can pick up at a hardware store.

They're easy to keep clean, I just boil mine for a few minutes when I'm pre boiling water.

I think with O2 the purity eliminates the need for a filter. I have an aquarium setup that came with an autoclavable inline filter. I hope to test this setup real soon.

[Tweek]

The o2 stone that comes with that setup has some absurd micron tolerance. I think a filter would be overkill. But far be it for me to come between a man and his toys, god knows I have a few of em.

[shughes600]

Originally posted by Tweek
The o2 stone that comes with that setup has some absurd micron tolerance. I think a filter would be overkill. But far be it for me to come between a man and his toys, god knows I have a few of em.

Yes it is .5 micron I think. The filter is not for that, but for airborne microrganisms and spoilage.

[shughes600]

Originally posted by S.F.B.
I like to take it another step further. I use an aquarium pump to get that extra bit of oxygen into the wort before I pitch the yeast. Since starting this, I have not had a lag time of more than 10-12 hours.


S.F.B.

I was wondering a little about your setup. I obtained an aquaruium pump setuop with a tiny (1/4"?) stainless tube that the stone attaches to. I had planned to insert this rod through a carboy cap (the ones with two hole, the smaller of the two would be a perfect fit for my tube). I changed my mind because I wanted to use my heating belt which only works on plastic vessels (I have a hard time keeping my ale above 70 degrees in the basement). I drilled a suitable hole (which is surprisingly pressure tight) through the lid of my bucket and inserted the steel tube. The problem i am having is that I fill the headspace of the bucket with foam and blow it out the blowoff I am using rather quickly. A few hours ago I heard a loud pop. This was the lid of my bucket blowing off. It actually unseated itself; no mess thankfully. Do you have a large amount of foaming with your aerator? What is your rig?

[paul84043]

Wow, you must be building some serious pressure to blow the lid off...
So you're just pumping air? For how long?
The nice thing about the oxygen setup is that you only do it for one minute. Even at that, it builds quite a bit of foam...

[Tweek]

I dont know if I am just reading this wrong, but you shuoldnt have the container sealed when you are aerating. You will build up pressure and can have the lid or seal break. I just dangle my stone in through the mouth of my carboy and kinda swirl the carboy while I pump the air in.

[shughes600]

I built some serious pressure. I had the bucket vented via a 1/4" ID hose. The lid popped after a half hour of running. Earlier in that same day I left the aerator running for 1 1/2 hours with nothing in the vent hole of the bucket. I came home to a bucket with 3" of foam on top of it.

I am just pumping air. I have very serious fermentation at 18 hours with no yeast starter (3-4 bubbles a second). I will assume I had about a 6-8 hour lag time.

I could see using my plain air system for only 10 minutes every hour for the first six hours based on this experience.

I was just wondering what routine others used.

[Tweek]

Shughes600, That is way too much air. You should only use your stone for like 2 bursts of 10 seconds or so 1 1/2 hours can bring about problems such as high ending gravites.

[paul84043]

Pure oxygen for 1 minute, before pitching yeast. Most of my batches are going like hell within 8 to 10 hours.

[shughes600]

Originally posted by Tweek
Shughes600, That is way too much air. You should only use your stone for like 2 bursts of 10 seconds or so 1 1/2 hours can bring about problems such as high ending gravites.

Tweek,

Are you absolutely sure on this. I checked Dave Miller's HOMBREWING GUIDE - everything you need to know to make great-tasting beer. He recommends aerating for 20 minutes to reach saturation, and he says to use a valve to throttle the flow thus limiting foaming. He cautions to limit the rates when using pure O2. I am using air. Air saturated wort is ~8.5 ppm O2. All resources I have seen indicate a level near 40 ppm will cause O2 to damage the yeast as it has reached sanitation levels. I would agree with your procedure for pure O2.

Here is a link to BYO BYO - Mr Wizard on aeration (http://www.byo.com/mrwizard/1074.html) It is very good, but talks about pure O2 and yeast propogation (unpitched I believe).

BTW the book I mentioned was an excellent read. Much better than any I have (many) on the mechanics of brewing. He covers everything. The complete joy of homebrewing was great for beginning but constanly left me wondering about what was next.

[shughes600]

Tweek,

I was looking for something on B3. I found the following.

Instead of diffusing pure oxygen into your wort this system uses filtered air. The included air pump pushes air through an inline sanitary filter. The filtered air is then dispersed into the beer through our two micron stainless steel diffusion stone. The advantage of an aeration system is that you never have to buy replacement oxygen tanks. You buy this system once and you are done. The down side is that it takes longer. Because the atmosphere is only about 20%, the diffusion stone must be left running in the wort for approximately 30-120 minutes. There is no concern of contamination during this period, however you do have to monitor the fermenter periodically for possible over foaming.

[paul84043]

I don't know....one bottle of oxygen should last me a long time only running one minute per batch...and they only cost about 10$.

If have already done 12 batches with it, say I get 30 before it runs out, ( I still should get alot more than that, I'm guessing a hundred or so, you just barely crack the valve open)
I would have cost me .33 cents per batch, that's less than a half a cent per beer. And that's at 30 batches, If I get 60 or 100 then the price really drops into the range of wondering why I would even consider it at all.

[Tweek]

Ahh yeah my bad I thought you were using pure o2.

[paul84043]

Okay....Pure is a subjective term I guess!

I just pick up the red Oxygen bottles at home depot....

[Tweek]

Those are pure (well pure enough for this context). That is what I use as well.

[shughes600]

The only good reason I went with the aquarium pump and atmosphere was an ignorance to the availability of pure O2. Wish I had gone the pure O2 route. Seems like less headache.

[Tweek]

its not too late, the stone will only run ya about 20 bucks and each cylinder is in the 5-10 range depending on where you get it.

[shughes600]

From what I have seen I should be able to use my stone, but I'd need a regulator, no?

[shughes600]

Good News. In my never ending quest to make the perfect beer I may have stumbled onto something. I was looking for an inline aerator to simplify things. I got to thinking about aerating in the boil kettle. Today I was brewing outside and got quite a few intruders to my kettle prior to putting a lid on it. After I got the wort down to 90F (immersion chiller) I inserted my sanitized aerator and built a huge head of foam. The foam formed a boundary layer while I siphoned the goodies from below. I had a bubble a second fermentation within 8 hours.

[Tweek]

Shughes, no you dont need a regulator. just a way to turn it off and on. the pressure that is in the o2 cans is fine and does not need to be dialed down.

You aerating in the brew pot sounds like a good idea. The only problem that I could see is that all the floaties (hops ect) that have settled during cooling would then get stirred up and would then end up in your fermenter. Did you see more trub end up in your fermenter using this method?

[shughes600]

I couldn't say. I siphon into a strainer with a mesh screen, which catches all my hop residue. Will trub pass through a fine nylon strainer?

[Tweek]

dunno. but I doubt it. I am going to have to give that method a try. I just need to fashion a filter.

[paul84043]

I don't have the equipment to take the wort off the bottom of the boil kettle, I have to pour it through a collander and a fine mesh strainer, but I can see all kinds of benefits to what you discovered, a nice layer to keep the wort clean as you remove it from below...
My lag times are averaging about 8 to 10 hours before the first signs of fermentation and another 4 to 5 before things are going crazy.
Some say that adding oxygen can even increase your lag time, I have been doing some reading and do believe that this may well be true.
The yeast will continue to multiply and grow until all of the available oxygen and glucosamine is consumed, that is before it ever starts to go to work on the wort at all. It's actuall the lack of oxygen that signals the beginning of the feeding frenzy, which is basically the yeast fattening up preparing to go dormant again. Now we all know that alot of them never make it, they die well before the food supply is consumed, that's just the way it goes when you're a yeast!

Anyway, my point being that more oxygen= more multiplying and growing (a little tiny Soddom and Gommorrah)= longer lag time, relatively speaking..... probably not for the same reasons that cause lag time in unoxygenated wort.
But the huge upside is that when they get going, there's a massive population ready to kick some wort butt!

[shughes600]

I just used a racking cane, a hose, and good old fashioned gravity to transfer the wort out of the kettle.