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Posted: Mon Apr 13, 2015 9:11 am
by matt7215
ercousin wrote:
matt7215 wrote:just mashed in a big imperial stout:

16 lbs 2 row
1 lb black patent
2 lbs chocolate malt
1.5 crystal 40
2 lbs dark munich

3 oz centenial at FWH
3 oz centenial at whirpool

huge cake of S-04

target OG is 1.119
Did you end up undershooting OG? That doesn't look like enough grain once you take into account the decreased efficiency of larger grain bills. I usually shoot for ~63% when I go that high in OG. 75% around 1.050.
I hit my target OG, boiled down to 4.5 gallons to hit it.

I had this calculated at 75% efficiency for the big grain bill. my normal batch (1.050) efficiency is usually around 90%

Posted: Mon Apr 13, 2015 1:30 pm
by Derek
atomeyes wrote:
2 curious questions for you

1. oxygen stone to aerate?
2. will you re-oxygenate at 24 hrs?
I've never done a brew this big, but oxygenation is really for yeast growth. If you're pitching it on a healthy cake, I don't think it's necessary.

Posted: Mon Apr 13, 2015 2:07 pm
by matt7215
atomeyes wrote:
matt7215 wrote:just mashed in a big imperial stout:

16 lbs 2 row
1 lb black patent
2 lbs chocolate malt
1.5 crystal 40
2 lbs dark munich

3 oz centenial at FWH
3 oz centenial at whirpool

huge cake of S-04

target OG is 1.119
2 curious questions for you

1. oxygen stone to aerate?
2. will you re-oxygenate at 24 hrs?
no, i wont add oxygen at either time.

ive never brewed a beer this big but my neighbor Scott brews some excellent high gravity beer so im leaning on him for a lot of process advice.

Posted: Fri Apr 17, 2015 11:01 pm
by atomeyes
Derek wrote:
atomeyes wrote:
2 curious questions for you

1. oxygen stone to aerate?
2. will you re-oxygenate at 24 hrs?
I've never done a brew this big, but oxygenation is really for yeast growth. If you're pitching it on a healthy cake, I don't think it's necessary.
yeast growth isn't my forte. but oxygen never hurts yeast growth, so my not O2 it?
healthy yeast still needs O2 for proper growth. simple shaking may not give enough O2 for healthy growth, even if the cake is healthy.

Matt: lots of US breweries pump O2 in again at 24 hrs to give the yeast another push. i'm going to start to do this for beer over 10% abv.

Posted: Fri Apr 17, 2015 11:02 pm
by atomeyes
i brewed a Chimay-inspired quad today.

tomorrow, helping a friend with a lambic (no turbid mash).

this week, i'll do an IPA

Posted: Sat Apr 18, 2015 4:23 pm
by J343MY
I brewed an IPA with mostly citra and a little amarillo today.

Posted: Wed Apr 22, 2015 1:12 pm
by JasonTremblay
atomeyes wrote:
Derek wrote:
atomeyes wrote:
2 curious questions for you

1. oxygen stone to aerate?
2. will you re-oxygenate at 24 hrs?
I've never done a brew this big, but oxygenation is really for yeast growth. If you're pitching it on a healthy cake, I don't think it's necessary.
yeast growth isn't my forte. but oxygen never hurts yeast growth, so my not O2 it?
healthy yeast still needs O2 for proper growth. simple shaking may not give enough O2 for healthy growth, even if the cake is healthy.

Matt: lots of US breweries pump O2 in again at 24 hrs to give the yeast another push. i'm going to start to do this for beer over 10% abv.
Hey, a nerdy question!

Big beers are stressful on yeast. Stressed yeast kick off fusels (often bad, but some people like the warming sensation in a big beer), phenolics (depends on the strain, can be good, bad, or good until it gets overwhelming and then bad), esters (see "phenolics"), and otherwise off-flavoured beer (bandaid, nail polish). Stressed yeast also don't attenuate very well. Well-aerated yeast are usually better able to deal with a stressful environment.

Which brings us to secondary aeration (not even sure if that's a word). The thinking is that by aerating on the second day, you're basically giving yeast a second wind so they don't end up quite so stressed and ill-behaved. Usually when people talk about this, they're trying to get the maximum attenuation possible (although, to be fair, some people like their big beers sweet). For a really nerdy side-track, this is also why forced fermentation tests are done on stir plates and shaker tables.

FWIW, I think O2 stones are a PITA to deal with on the homebrew scale. I just use the liquid line on a soda keg (I use kegs with cut dip tubes as fermenters) with a poppet, some hose, a sterile air filter (both big stores have them) and an aquarium pump. You can't realistically over-aerate with air, so you can leave it do its thing for a half hour or so while you do some cleaning. Although I'd recommend a couple drops of defoamer.

Posted: Wed Apr 22, 2015 2:10 pm
by ercousin
JasonTremblay wrote:You can't realistically over-aerate with air
You also can't aerate enough with only air, theoretically. For something high OG you want much more than the 8 ppm max you get with air, closer to 12-16 ppm would be better, which needs pure O2. A 2nd aeration after 12-18 hours would help mitigate this of course. I think a carb stone, filter, regulator, and CDN Tire O2 tank is a much simpler setup than having to plug in an aquarium pump. O2 wands tend to be designed with carboys in mind though, so aerating into a keg with one could be a pain.

Posted: Wed Apr 22, 2015 3:56 pm
by atomeyes
i'm with eric on this.

but jason, just wondering what's a pain about O2 stones? just don't touch the stone and it's fine. rinse immediately after and it's fine. sanitize first and it's fine.

Posted: Wed Apr 22, 2015 3:58 pm
by ercousin
atomeyes wrote:i'm with eric on this.

but jason, just wondering what's a pain about O2 stones? just don't touch the stone and it's fine. rinse immediately after and it's fine. sanitize first and it's fine.
And even if you do manage to gum it up, just boil it.

Posted: Fri Apr 24, 2015 2:14 pm
by JasonTremblay
atomeyes wrote:i'm with eric on this.

but jason, just wondering what's a pain about O2 stones? just don't touch the stone and it's fine. rinse immediately after and it's fine. sanitize first and it's fine.
Dry yeast doesn't need O2 (seriously, it's in the spec sheet the manufacturers give to brewers). That, the cheap price (less than $2 a pack, bulk), decent quality, and improving selection make me look at the flask, stir plate, and DME and go, "Nahhhhh."

Otherwise, stones are just one more fiddly bit to keep clean.

If I really want to use a strain I can only get "wet", I like my cornie aerator since I can walk away from it for hours while I go do something else. And nothing touches the beer that otherwise wouldn't (the dip tube has to be clean anyway). Everything else, from the pump, filter, hose, and quick connect stays clean.

FWIW, I've used stones for years. I know they work. And I know firsthand that one tank of O2 should last a homebrewer years. But ... I want my brew days to be fast. Starters and aeration just add time to a part of the process I don't want to be bothered with.

Posted: Fri Apr 24, 2015 2:37 pm
by JasonTremblay
ercousin wrote:
JasonTremblay wrote:You can't realistically over-aerate with air
You also can't aerate enough with only air, theoretically. For something high OG you want much more than the 8 ppm max you get with air, closer to 12-16 ppm would be better, which needs pure O2. A 2nd aeration after 12-18 hours would help mitigate this of course. I think a carb stone, filter, regulator, and CDN Tire O2 tank is a much simpler setup than having to plug in an aquarium pump. O2 wands tend to be designed with carboys in mind though, so aerating into a keg with one could be a pain.
I don't ferment in carboys anymore :)

So, I did some poking around and hauled out my copy of Yeast from White and Zainasheff. In general, yeast does best with atmospheric levels of O2 (going above this tends to slow down the yeast). In the specific case of high gravity beers:
If it is a very high-gravity wort, more than 1.092, you must aerate with pure oxygen, as air will not provide a high enough level of dissolved oxygen.
Unfortunately, that still might not be enough for beers higher than 1.083. For high-gravity beers, adding a second dose of oxygen between 12 and 18 hours can help fermentation speed and attenuation ... Research also indicates the addition of oxygen (some say more than 7 ppm,, some say more than 12 ppm), at 12 hours increases the fermentation speed by 33 percent and decreases flavor compounds ... Why wait until 12 hours? You are waiting for the yeast to complete at least one cell division.
They also recommend rather large pitching rates and, after 48 hours, fermenting at 25C to keep the yeast at their most active.

IME, neither one of us scores a knockout. But the important bit, I think, is to aerate your wort since vigorous splashing for 5 minutes is less than 3ppm of oxygen, much less than the 7 or 8 you want with regular strength wort. Unless you go with dry yeast.

FWIW, the O2 wand you pictured is virtually identical to my system for aerating in a keg (down to the sterile air filter). The big difference is that I'll aerate for a half hour or more and don't bother with the stone.

Posted: Sun Apr 26, 2015 6:46 am
by atomeyes
made an IPA yesterday. hah.
me. made an IPA.
hopped the 1st runnings and then whirlpooled, tho.

Posted: Sun Apr 26, 2015 10:40 am
by J343MY
atomeyes wrote:made an IPA yesterday. hah.
me. made an IPA.
hopped the 1st runnings and then whirlpooled, tho.
I thought you hated IPAs?

Posted: Sun Apr 26, 2015 10:55 pm
by atomeyes
J343MY wrote:
atomeyes wrote:made an IPA yesterday. hah.
me. made an IPA.
hopped the 1st runnings and then whirlpooled, tho.
I thought you hated IPAs?
when you get married, you'll understand