Homebrewers Association | AHA Forum

General Category => Yeast and Fermentation => Topic started by: gimmeales on August 15, 2011, 05:06:58 PM

Title: Dry yeast (Rehydrated) pitching temps
Post by: gimmeales on August 15, 2011, 05:06:58 PM
Being one who usually hydrates his dry yeast (as it seems slightly preferred by the manufacturers) has raised a question for me when considering the temp of the re-hydrated yeast vs. that of the cooled wort.  Wouldn't pitching the yeast re-hydrated in ~80-ish degree into a wort in the mid-60's shock the yeast pretty good? 

Yeast fare better pitched into warmer wort and the above scenario is quite a difference in the other direction.  Being nervous I'll shock the yeast, I usually let the re-hydrated cream sit at room temp (maybe 30-45 mins) to better atemperate to the temp of the wort, but wondering if there's any other wisdom out there on this scenario? 

Cheers,
-Ryan
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: Malticulous on August 15, 2011, 05:11:47 PM
I pitch about every ale at 59-60F. I haven't worried much about shocking the yeast. It's always going strong in less that 24 hours.
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: Pi on August 15, 2011, 05:15:03 PM
What about lagers? The liquid Weast say itcch around 75f than cool to lager temp ~55...
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: captvideo on August 15, 2011, 05:16:54 PM
I agree with Maticulous. I rehydrated 3 packs Nottingham at 95F. Left it sit for about 30 minutes then pitched into 10 gallons of wort which was at 77F. I had vigorous (and I do mean vigorous) bubbling within 6 hours.
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: denny on August 15, 2011, 05:19:15 PM
While yeast may like being pitched into warmer wort, beer flavor generally does not.  My experience is that the beer turns out much better if I pitch when the wort is in the low 60s, in general.  Also, pitching warmer yeast into cooler wort can be a bad idea (I understand), but cooler yeast into warmer wort can be a good thing.  I'd cool down your rehydrated yeast so that it's below the temp of the wort before pitching.
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: denny on August 15, 2011, 05:21:30 PM
What about lagers? The liquid Weast say itcch around 75f than cool to lager temp ~55...

Bad idea, in my opinion based on my experience.  Cool your lager to a bit below your fermentation temp, then pitch.  My results have been much better since I started doing that.
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: gimmeales on August 15, 2011, 09:15:18 PM
Thanks all.  I've not had issues with off or slow fermentations, so I'm assuming I'm fine, but seem to remember attemperating the yeast to the wort's temp (+\- 5F) as being stressed as optimal in a podcast at some point and just started thinking about it more. I'm usually within ~5F of  wort temp with my yeast cream.

I'm with you Denny on low 60's pitching - I like that too, but got me thinking that my neither my dry yeast or liquid starters are that cool at pitching, I'll have to play around with cooling them down and see what transpires..
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: Malticulous on August 15, 2011, 11:42:56 PM
What about lagers? The liquid Weast say itcch around 75f than cool to lager temp ~55...
They are also talking about pitching only one pack. You need more like four to pitch at 48 (or two packs of dry yeast.). I step up a 2L starter to near one gallon and pitch them at 48-50F. Most of my lagers are at FG in 7-10 days.
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: ynotbrusum on August 23, 2011, 06:15:51 PM
I don't see why the manufacturers don't want to sell more yeast, but for some reason, they don't estimate the lagers correctly according to Jamil's program.  I would rather have a vigorous fermentation than a sluggish one (admittedly, some beers will taste fine even if underpitched slightly and certain styles are best underpitched).  So cooling both the wort and the yeast to below fermentation temperatures and then pitching at or above the right amount of cells and allowing the temperature to rise to the correct temperature always seems to work best for me.
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: Hokerer on August 23, 2011, 06:58:31 PM
So cooling both the wort and the yeast to below fermentation temperatures and then pitching at or above the right amount of cells and allowing the temperature to rise to the correct temperature always seems to work best for me.

Regardless of what the manufacturers say, what you describe is the correct way to do it.
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: a10t2 on August 23, 2011, 07:18:54 PM
I don't see why the manufacturers don't want to sell more yeast

That continues to absolutely baffle me.
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: tschmidlin on August 24, 2011, 06:13:34 AM
It's not that they don't want to sell more yeast, it is that the customers balk at the price they have to pay for enough yeast.
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: ynotbrusum on August 24, 2011, 09:46:28 PM
It's not that they don't want to sell more yeast, it is that the customers balk at the price they have to pay for enough yeast.

Yes, but then why refer to it as a "sufficiently pitchable number of cells", when sometimes (lagers, e.g.) it is woefully inadequate?  Why not sell it as a starter level for 5 gallons and encourage the use of starters?

Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: denny on August 24, 2011, 10:07:11 PM
It's not that they don't want to sell more yeast, it is that the customers balk at the price they have to pay for enough yeast.

Yes, but then why refer to it as a "sufficiently pitchable number of cells", when sometimes (lagers, e.g.) it is woefully inadequate?  Why not sell it as a starter level for 5 gallons and encourage the use of starters?



Because that makes things harder for some brewers.
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: tubercle on August 24, 2011, 10:20:45 PM
Why not pitch dry directly out of the refridgerator like Tubercle does.

One less thing to worry about.

Just a suggestion.
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: Hokerer on August 24, 2011, 11:33:12 PM
Why not pitch dry directly out of the refridgerator like Tubercle does.

Ummm, selection?
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: tubercle on August 24, 2011, 11:45:08 PM
Why not pitch dry directly out of the refridgerator like Tubercle does.

Ummm, selection?

 I was refering to the OP's delimma of hydrating yeast and concerrn of yeast slurry temp vs. wort temp.

 I select the yeast I'm going to use out of the refrigerator and sprinkle on the cooled and aerated wort.

I don't understand your comment/question.
Title: Re: Dry yeast (Rehydrated) pitching temps
Post by: Hokerer on August 24, 2011, 11:50:29 PM
I don't understand your comment/question.

My misunderstanding.  I'd been reading the posts in this thread about "sufficiently pitchable number of cells" and manufacturers claims and such so I had liquid yeast on my brain.