Areating Wort After Putching?!?

[Ade42]

from the fermentis web site

Alternatively, pitch dry yeast directly in the fermentation vessel providing the temperature of the wort is above 20C. Progressively sprinkle the dry yeast into the wort ensuring the yeast covers all the surface of wort available in order to avoid clumps. Leave for 30 minutes and then mix the wort e.g. using aeration.

Ok does that mean i should wait 30 mins after pitching and unscrew the lid. give the wort a good thrashing, and screw back up and stick in fridge?.

I don't get the Aeration word!

and ive just read about 20-40 treads on Pitching and none seem to awnser this question, Im a kit and kilo guy and have no "Fancy" gear like a "stirrer plate?!?" so how should i pitch?.

Ive just poured out a fine lagar made with some nice hops and grain as adins which stalled at 1020 which could have been to me pitching the thing at 11 c!

 

[manticle]

I'm guessing that's an alternative to rehydrating?

 

[Acasta]

Well when using fermentis US-05, i sprinkle the dry yeast over the top of the wort, screw on the lid and walk away. No problems yet.

 

[Ade42]

I'm guessing that's an alternative to rehydrating?

Yep, But the last instruction about going back to your fermenter and "aerating" 30 mins later worrys me!!


For this beer since i now have "cooling technology" (fridge) Id follow all instructions. and im still baffeled.

Would that be the worst thing to do to a just pitched wort, stir it up?

 

[manticle]

No. Aerating beer when it's actively fermenting is not a good idea. Nor is it a good idea to aerate once it's finished.

however, adding yeast in then aerating within a short period of time should be fine (and desirable).

My very basic understanding of it is that aerating before the beer is actively, visibly fermenting is fine as the yeast is in its growth phase (in the main - all phases cross over at some point). Once it has moved from this phase, aeration is problematic but that should be a fair bit after 30 minutes (between hours and days depending).

 

[kelbygreen]

you can aerate by stirring vigorously. I just pour wort in screw the lid on shake the hell out of the fermenter then take a hydro reading and then sprinkle yeast in as shaking it aerates the wort. you can also get a pump and a air stone and do it that way if your really worried. never had trouble sprinkling onto I only shake it to get my OG as found that if you dont stir or shake well you will get a higher og as its not mixed properly

 

[glaab]

Putching?, u a kiwi? :unsure: , it's probably aerated adequately when you stir the crap outa it to mix the goo.
Pouring the water in from some height aerates it too. Just stir it in. Rehydrating as they recommend seems the best way, I've seen krausen about an hour or two after putching doing it that way with US05.

 

[Ade42]

Cool, Yeah Ive been for almost 2 years now just using my shower on "pulse" setting It aerates the crap outta the wort.
and have never had a prob with just sprinkling yeast on surface then sealing fermenter and waiting a couple of weeks.

The whole rehydrating scene freaks me out as i don't think I could stir for 30 min straight, nor do i have any Stir plate

 

[glaab]

I just give it a stir every 5 mins or so for 30mins. That's how Lallemand recommend to rehydrate, never read the Fermentis brochure closely enough to notice it was different. I leave the [sanitized] spoon in the pyrex dish throughout with gladwrap over it and don't remove the gladwrap when I stir it, I put it on loose enough but tight around the sides if that makes sense. I've just sprinkled it on top plenty of times and never had a problem either but it does reduce lag time if you rehydrate it.

 

[ginsoakedstranger]

When I started rehydrating I found whenever I would stir it a lot of yeast got stuck to the spoon and was impossible to get off, seemed like a waste. Now I just sprinkle the yeast evenly into 100ml of 35 degree water, cover with wrap, leave for 15 mins, give it a good swirl, leave for another 5, and I've got nice frothy yeasty goodness to pour in the fermenter. Stir plates aren't neccessary unless your making a 'yeast starter', which is different.

Getting back to the OP, don't stress too much man. Give it a good shake for a couple of mins in the fermenter, take a the OG reading, sprinkle your yeast over the top, lid on, give it a swirl. It'll start no probs at 20 degrees.

 

[Bribie G]

If you are using kits and tap water then the tap water is nicely oxygenated anyway, so no need to thrash it.

Later if you do All grain brewing, a good splash and thrash is good to get some oxygen into the wort, but some yeasts like more aeration than others. Most lager yeasts have less oxygen requirements than ale yeasts. Some ale yeasts such as the ones used in Yorkshire bitters actually do well if thrashed twice a day for a couple of days.
With US-05 I check the next morning, if it's starting to krausen then I give it a thrashing with a slotted (sanitized) spoon for about 30 seconds, seal it up and don't touch until finished off.

 

[Noxious]

'Most lager yeasts have less oxygen requirements than ale yeasts' - BribieG

I found this very interesting as I thought the opposite would be true as 'ale' yeasts would have developed during warmer fermentation(s), thus enduring lower dissolved oxygen concentrations.
While lager yeasts have the facility to ferment at lower temperatures, where higher concentrations of dissolved oxygen can be present.

Anyone else see what I'm getting at?
:blink:

 

[Bribie G]

Yes, I agree. Maybe I should have rephrased that as "lower aeration requirements" - possibly why top fermenting yeasts (which are largely UK strains) are traditionally used in open fairly shallow fermenting tanks and go to the top of the ferment like fish gasping for air

Oh goodo that gives me the opportunity to post this one again:



:beerbang:

Now I'm getting off topic

 

[Ade42]

Cool looks like ive been doing it right for a while then, using shower on pulse, just sprinkiling on surface etc.

Another interesting bit of the fermentis instructions is to get the wort to 20c before sprinkling on yeast.
Last one I put down I got to 11c then pitched the yeast. according to fermentis this is wrong!.

Ill be pitching at 20c and then leaving for an hour or so before transferring into fridge, But today's temps at 15 hardly make it worthwhile!

 

[ginsoakedstranger]

what temp is your fridge set too?

 

[kocken42]

At the winery I work at, we use aeration on the yeast starter for fresh white wines only...this is because white wines are kept in a reductive environment (as oxygen is white wine's biggest enemy!) and is therefore not exposed to oxygen throughout fermentation and also for weeks after. This is also similar to beer as after your initial stir of the wort, the beer is not exposed to oxygen. The reason why we aerate (with pure oxygen gas) the yeast starter is because in a highly anaerobic environment, the yeast may become 'sticky' or get stuck completely, so if you give the yeast plenty of oxygen after rehydration and during the food introduction, they are more likely to complete the ferment hassle free.

Although, after saying all of this, I have never had a stuck ferment in a beer before...I think it's just a safety net to ensure your yeast are given the best head-start possible!

 

[Ade42]

what temp is your fridge set too?

At the moment it's set for 13-14, closer to 14. inside the fridge right now (joys of a wirless temp monitor) 13.2 which its been for at least the last 6 hours since i Bunged in the 2 fermenters. I check the temp about 20 times a day!.

I was going to go for 12c or 11c but by reading loads of threads here, I thought Id stick to almost 14 (which is really 13!) I made the temp controller myself and am getting aware to its eccentricities.

As im using w34 and s23 in each fermenter I thought a happy 13c should do it, plus the last one i had at a rock steady 11-12c stalled

 

[kocken42]

As im using w34 and s23 in each fermenter I thought a happy 13c should do it, plus the last one i had at a rock steady 11-12c stalled

This is probably the exact reason they talk about aeration for the yeast after 30 mins, as 11-12 C temps is quite cold for a lot of microbes to survive. If you are going to ferment them in a cool environment, give them a real kick to start with.

 

[Synthetase]

But this is a lager yeast. Quite happy at those temperatures.

This is probably the exact reason they talk about aeration for the yeast after 30 mins, as 11-12 C temps is quite cold for a lot of microbes to survive. If you are going to ferment them in a cool environment, give them a real kick to start with.