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General Category => Yeast and Fermentation => Topic started by: yugamrap on December 06, 2018, 10:03:32 PM

Title: Starters - Pitch whole, or crash & decant?
Post by: yugamrap on December 06, 2018, 10:03:32 PM
For those of you who make starters, what is your practice and why?

Do you pitch the whole starter volume, or do you crash the starter and decant a smaller volume?

I pitch the whole volume if it's just a quick, small starter to "wake up" the yeast for an ale. 

For lagers, though, I often make a 1-gallon starter starting with 2 yeast packs (Mr. Malty's recommendation).  I do that at room temperature on a stir plate.  Then, I cold-crash the starter for about 24 hours and decant about 3/4 of the liquid before pitching.  I do this because the starter "beer" is often much different in character than the finished batch will be.  As well, I'm concerned about off-flavors - especially esters and acetaldehyde - from the starter making their way to the finished beer.  On the other hand, crashing and decanting aren't perfect - so I wonder how much good viable yeast from the starter I'm losing to this practice.

What's your practice and experience?  Recommendations?  Do I just need to relax, don't worry...?

 
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: Robert on December 06, 2018, 10:13:58 PM
I generally share your concerns.  Especially when it's been on a stir plate, the starter wort is something I don't want in my beer.  Really don't want significant amounts of any foreign wort in there.  I never thought I might be losing anything desirable in decanting.  Surely can't be significant, and the benefits are worthwhile.   If I were making what you call a wakeup starter,  I'd make sure to avoid the stir plate, and there shouldn't be any abnormal fermentation products to worry about.   But I usually just complete and decant on any scale, because I can't easily time starters for pitching at high kräusen.

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Title: Re: Starters - Pitch whole, or crash & decant?
Post by: yugamrap on December 06, 2018, 10:30:01 PM
Rob - I saw on another thread that you reuse yeast harvested from the 10-gal corny in which you ferment.  Do you just harvest after pushing the batch to a serving or lagering keg?  How long is "too long" for you such that you'd choose not to harvest?  When you harvest, do you just jar and refrigerate the slurry, or do you wash it?

I'm curious about harvesting/reusing yeast because I'm brewing more lagers and wouldn't mind saving a few bucks on purchasing yeast if I can harvest and reuse successfully.

Could we get you to a SNOB meeting sometime to do a presentation on harvesting/reusing yeast?       
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: narcout on December 06, 2018, 10:30:47 PM
Do you pitch the whole starter volume, or do you crash the starter and decant a smaller volume?

I've pitched a full 1 litre starter at high krausen several times, and it works fine.  However, my personal preference is to chill, decant, and just pitch the slurry.

I don't think either way is inherently better.  You might pick one over the other based on timing, circumstances, particular goals, etc.

Title: Re: Starters - Pitch whole, or crash & decant?
Post by: Robert on December 06, 2018, 10:41:31 PM
I transfer the beer to keg, then swirl up slurry and pour some into a Mason jar, loosely covered.  I used to rinse because that was conventional homebrew wisdom,  but have learned it's actually quite harmful and it's better just to keep it under the beer it made.  I usually am able to reuse within a week,  but I gather others store yeast much longer.   A little yeast in a jar is subjected to much less stress (temperature,  pressure etc.) than under commercial conditions.

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Title: Re: Starters - Pitch whole, or crash & decant?
Post by: RC on December 06, 2018, 10:43:05 PM
I only do vitality starters (which is the same, I think, as what you're calling wake-up starters). I use a stir plate and a foam stopper. I want the yeast to have O2 to build those cell membrane components. That's part of the "waking-up" process. I give the starter about 4-5 hours before pitching into the main wort. I also don't have to add O2 to my main wort doing it this way, as the cells will already have had ample O2 in the starter wort. I pitch the whole starter, since I'm not giving the yeast any time to settle. But this is not a concern. Since this is just a vitality starter, it's only about one liter of starter wort, which is negligible in a 6 gallon batch. I've had great success doing starters this way, I highly recommend giving it a try.
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: TeeDubb on December 07, 2018, 04:37:03 AM
I used to use do a traditional ~1.5L starter on a striplate using DME or leftover (previously frozen) wort. I would prepare the starter a few days before brew day, cold crash, and then usually pour off most of the liquid, stir to agitate the yeast cake and pitch.  This forum led me to the 'shaken not stirred' or SNS method.  I have used this a few times now and it has worked very well.  There is much less hassle in the days leading up to brew day and my fermentations take off very quickly now (4-12 hours).  You can read about it on these threads:

https://www.jimsbeerkit.co.uk/forum/viewtopic.php?t=70926 (https://www.jimsbeerkit.co.uk/forum/viewtopic.php?t=70926)

https://www.homebrewersassociation.org/forum/index.php?topic=24447.0 (https://www.homebrewersassociation.org/forum/index.php?topic=24447.0)

I will probably sell my stirplate - no going back! The benefits seem to be significant and I like the idea of pitching a starter that is at high krausen.  FYI - I now pitch the whole starter since the cold crash step is skipped. Give it a try and see what you think.
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: Richard on December 07, 2018, 06:04:16 AM
For many brews I used a stir plate to make starters which were refrigerated and decanted. Earlier this year I decided to try the "Shaken Not Stirred" approach instead. I pitched the yeast into 1 liter of DME-based wort in a 1-gallon (nice mixture of metric and English units) container the night before, then pitched the whole mess into the wort on brew day. This was easy, but I didn't see any decrease in lag time or any increase in activity or beer quality. I tasted the mixture before pitching on one brew and decided I didn't want a liter of that stuff going into my beer. I am back to traditional starters with a modification. I cold crash and decant, but at the start of brew day I take the decanted yeast out of the refrigerator and add a small amount (~250 ml) of wort saved from making the starter. By the time I am ready to pitch it, the yeast is awake and producing CO2, although perhaps not at high krausen. I feel better about pitching this smaller amount of "beer" than I do about pitching 1 liter of SNS "beer". Neither tastes particularly good, but at least the quantity is smaller the way I do it now.
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: kramerog on December 07, 2018, 07:38:07 PM
I do the traditional decant.  I'm going to start to add spent yeast to the boil of the starter as a source of nutrients particularly zinc rather than to the wort to take advantage of my practice of decanting.
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: denny on December 07, 2018, 07:55:32 PM
I do the traditional decant.  I'm going to start to add spent yeast to the boil of the starter as a source of nutrients particularly zinc rather than to the wort to take advantage of my practice of decanting.

Actually, traditional is pitching the whole thing.  Decanting is a relatively recent thing.
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: Erik Nordwald on March 10, 2019, 07:25:41 PM
Hi All,
I work in biopharma doing bacterial fermentations but am rather new to the homebrew game. Seems to me the healthiest yeast would be pitched in the heart of exponential phase, and ideally with a pH and temperature that matched the wort into which you are pitching. Of course there is leeway there. A cold crash would still accomplish increasing yeast count, however.

I understand the concern of putting biproducts from the spent starter into your beer which is why people decant. What about centrifuge pelleting the yeast at peak growth and resuspending before pitching? Would the yeast be sensitive to g-forces in pelleting? Or potential shear during resuspension?

Anyone recommend a good book on yeast physiology?
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: denny on March 10, 2019, 08:15:25 PM
Hi All,
I work in biopharma doing bacterial fermentations but am rather new to the homebrew game. Seems to me the healthiest yeast would be pitched in the heart of exponential phase, and ideally with a pH and temperature that matched the wort into which you are pitching. Of course there is leeway there. A cold crash would still accomplish increasing yeast count, however.

I understand the concern of putting biproducts from the spent starter into your beer which is why people decant. What about centrifuge pelleting the yeast at peak growth and resuspending before pitching? Would the yeast be sensitive to g-forces in pelleting? Or potential shear during resuspension?

Anyone recommend a good book on yeast physiology?

Hi Erik,

While you are likely technically correct,  in reality is isn't that big a problem.  I recanted for years.  Now I don't and frankly it hasn't had an adverse effect on my beer.  As I like to say, "reality often astonishes theory".  This is the method I now use....https://www.experimentalbrew.com/blogs/denny/old-dognew-tricks
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: Robert on March 10, 2019, 08:30:06 PM
^^^^
He formerly decanted, but since has recanted.   ;D
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: denny on March 10, 2019, 08:43:40 PM
^^^^
He formerly decanted, but since has recanted.   ;D

Clever!
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: ynotbrusum on March 11, 2019, 02:03:17 AM
The shaken not stirred approach has gained widespread acceptance, for sure.  Alternatively, you can time your brewing for harvest and repitch on the brew day.  That has been my approach for the last couple years, averaging 7-8 generations per strain.
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: Robert on March 11, 2019, 02:15:05 AM
The shaken not stirred approach has gained widespread acceptance, for sure.  Alternatively, you can time your brewing for harvest and repitch on the brew day.  That has been my approach for the last couple years, averaging 7-8 generations per strain.
As I often note (drone on about,) storing yeast for a period before pitching or repitching is not a real problem either for us, if scheduling brewdays to match propagation or harvest is difficult.  The enemies of yeast in storage are hydrostatic pressure and heat buildup in the yeast mass generated by its own metabolism.   These are significant concerns in the cone of a commercial fermenter or even in a large brink.  In a quart jar in your fridge, or even on the bottom of a homebrew sized fermenter,  not so much.  One of many advantages we have over the pros.

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Title: Re: Starters - Pitch whole, or crash & decant?
Post by: ynotbrusum on March 11, 2019, 02:37:19 AM
For sure and agreed.  My reason for immediate repitch is lowering the likelihood of contamination, which, given my bumbing lab skills is appreciably increased with time in the flask!  YMMV for sure.  FWIW the most I have taken out a yeast strain was 25 generations.  I gave up because I tired of the strain at that point....
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: Robert on March 11, 2019, 02:41:52 AM
For sure and agreed.  My reason for immediate repitch is lowering the likelihood of contamination, which, given my bumbing lab skills is appreciably increased with time in the flask!  YMMV for sure.  FWIW the most I have taken out a yeast strain was 25 generations.  I gave up because I tired of the strain at that point....
Sounds like me, I think it was around 18 generations.  But that was harvesting and repitching about 5-6 days later, still no problem.   BTW that wouldn't have been WY2124, would it?

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Title: Re: Starters - Pitch whole, or crash & decant?
Post by: ynotbrusum on March 11, 2019, 12:00:09 PM
White Labs 830, but yeah Weihenstephaner.
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: Robert on March 11, 2019, 12:03:22 PM
Yep.  Workhorse, reliable, forgiving, versatile, and I just don't love it anymore.

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Title: Re: Starters - Pitch whole, or crash & decant?
Post by: Visor on March 12, 2019, 04:15:13 PM
The shaken not stirred approach has gained widespread acceptance, for sure.  Alternatively, you can time your brewing for harvest and repitch on the brew day.  That has been my approach for the last couple years, averaging 7-8 generations per strain.
As I often note (drone on about,) storing yeast for a period before pitching or repitching is not a real problem either for us, if scheduling brewdays to match propagation or harvest is difficult.  The enemies of yeast in storage are hydrostatic pressure and heat buildup in the yeast mass generated by its own metabolism.   These are significant concerns in the cone of a commercial fermenter or even in a large brink.  In a quart jar in your fridge, or even on the bottom of a homebrew sized fermenter,  not so much.  One of many advantages we have over the pros.

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   I have become hypersensitive to autolysis, can't detect diacetyl or DMS if I'm swimming in them but two dead decomposing yeasties in a gallon of beer and I'll notice them. That being said, depending on the yeast strain and batch specifics, I've detected autolysis in harvested yeast stored under beer in a closed jar in the fridge in as little as 10 days, though some harvests are still fine after 3 or 4 weeks.
Title: Re: Starters - Pitch whole, or crash & decant?
Post by: Ronnal on March 17, 2019, 08:01:39 PM
As a general rule, I crash my starter, but I do it to taste the beer before I pitch. It gives me an idea that the yreast is healthy and produces flavours and aromas I am happy with. If I am happy with it, I pitch the hole thing in.