Why do people chill their yeast starters?

[Elysium]

I have been wondering why people chill yeast starters for 24 hours before pitching? Maybe because they want to decant the used liquid that is on top of the yeast cells....I really dont know. But if that's the case, then the active yeast cells go dormant overnight in the fridge and pitching yeast cells that will have to become active again is rather silly, isnt it?

Isnt it easier to pitch the yeast cells without chilling and decanting after 16-24 hrs.....since those cells are actively eating the sugar away...meaning that what you pitch, just picks up the work that it was doing in the starter bottle.

By the way.....I am talking about normal gravity beers. So....in my case no massive starters are needed with loads of extra liquid.

Here is a video of my experimental yeast starter (1 UK pint, made from 90 grams of maris otter). I am putting it here...because I am wondering if you guys believe it would be a good idea to pitch yeast in this state? Look at it and you will see that it is active...after 16 hours of being on my table. I think if this is pitched, there wont be no fermentation lag...it would start almost immediately as soon as the yeast cells have reached the optimal reproduction level.

 

[unionrdr]

I chill them to get the yeast to drop & leave clear liquid. I can then pour off 3/4's of the clear liquid,leaving enough to swirl up the yeat & pitch it without the extra liquid diluting the batch of beer.

 

[Elysium]

I chill them to get the yeast to drop & leave clear liquid. I can then pour off 3/4's of the clear liquid,leaving enough to swirl up the yeat & pitch it without the extra liquid diluting the batch of beer.

Exactly. That's what everyone seems to be doing...but if it is a 1 UK pint starter, the liquid wont really affect the overall taste of the final beer and you can pitch yeast cells that are actively eating sugar away. Why would anyone want them go dormant in the fridge? This is what puzzles me.

By the way....thanks for the reply.

 

[Rake_Rocko]

Yes the reason people chill a starter is to let all the yeast fall out of suspension, decant the beer on top, swirl around to get all the yeast cake back in suspension and then pitch that.

Also, 24 hours of chilling won't cut it. You have to put it in the fridge 2-3 days before pitching so you can get all that yeast out of suspension.

As far as pitching a whole starter at high fermentation, you can most definitely do that as well. I have done both ways quite a bit and both with great success. People get paranoid about throwing in a beer that is made of nothing but light DME.

 

[Jaybird]

Some do and some don't. It depends really on if your going to step it up again. If so then chilling for a few days to drop the yeast and decant the majority of the beer off the yeast is helpful in getting another starter going.

Cheers
Jay

 

[grathan]

I like to get a visual on yeast amount produced. Timing isn't as critical either because you can leave it in the fridge for weeks.

Chilled active yeast cells arent dormant after only a day in the fridge.

 

[spyder2723]

Also in most cases the starter is to get the yest cell count up, not necessarily to pitch highly active yeast. In my case I like to decant the liquid off a starter, big or small. The small starters are usually used in beers that might not have as much going on in the flavor profile and I would prefer to avoid tossing in a liter of skunk "beer". And on larger beers adding 4 liters of starter doesn't seem like a good idea.

 

[two_hearted]

I do an overnight starter and pitch all of it at high krausen. I want my yeast awake, alive and ready to chomp!

I believe that is what Jamil Z advocates as well.

 

[Rake_Rocko]

I just saw your reply to union, and (as I'm sure you know this) you don't pitch the yeast right out of the fridge. You have to let it warm up naturally to room temp first. Also, putting them back in suspension rouses the yeast from their dormancy, especially in room temp liquid.

 

[progmac]

i agree that if you are just doing a pint or two, the best bet is pitching at high krausen.

when you're doing a 3-4 liter lager starter, it is a different story.

 

[Elysium]

Yes the reason people chill a starter is to let all the yeast fall out of suspension, decant the beer on top, swirl around to get all the yeast cake back in suspension and then pitch that.

Also, 24 hours of chilling won't cut it. You have to put it in the fridge 2-3 days before pitching so you can get all that yeast out of suspension.

As far as pitching a whole starter at high fermentation, you can most definitely do that as well. I have done both ways quite a bit and both with great success. People get paranoid about throwing in a beer that is made of nothing but light DME.

Hey Rake.
I use 90 grams of MO to make my 1/2 pint starter. So....I am not too paranoid. I am more interested in getting highly active yeast into the pitch...than slightly dormant cells. That is why I started the thread.

 

[two_hearted]

Also in most cases the starter is to get the yest cell count up, not necessarily to pitch highly active yeast. In my case I like to decant the liquid off a starter, big or small. The small starters are usually used in beers that might not have as much going on in the flavor profile and I would prefer to avoid tossing in a liter of skunk "beer". And on larger beers adding 4 liters of starter doesn't seem like a good idea.

It think it depends on your gravity. I think pitching highly active yeast is just as important as getting the cell count up. Also, how is your starter getting "skunky"? Unless you hop it and leave it in the light... I don't buy the old line that starter beer is oxidized and skunky. I think it is highly oxygenated and the yeast will scrub out anything else. You oxygenate your wort before pitching, right? I don't see a single downside to pitching the whole starter in an ale. Lager, I can see some reasons.

i agree that if you are just doing a pint or two, the best bet is pitching at high krausen. when you're doing a 3-4 liter lager starter, it is a different story.

I agree.

 

[Randy_Bugger]

I pitch the entire starter. I use a stir plate, so my starters are 1L-2L. If I had to use a BIG starter, like more than 2L in a 5G batch, I'd chill and decant.

Some people don't pitch the whole starter because they tasted the starter, thought it tasted or smelled bad and determined bad tasting things should not go in the beer. Some think pitching the whole starter makes the beer watery. Some don't want the starter to change the color of the beer.

I haven't found anything negative about pitching a 1L-2L starter. The beer tastes good and ferments properly. You also end up with more drinkable beer.

 

[kombat]

For small to medium ales, I pitch the entire starter (1 - 1.5 L) at high krausen.

For lagers or bigger ales, I chill and decant (3-4 L). This is not a choice - it's mandatory. After aerating 5 gallons of wort in a 6.5 gallon carboy, there is physically not enough room to add another 4L of liquid.

 

[unionrdr]

A half pint starter is a bit small for for getting the cell count up in any appreciable numbers. Getting them active again,yes. I use real small starters like that with older dry yeast to freshen them up again. Liquid yeast on average gets a 800mL to 1000mL starter from me. Maybe 5 days in advance if I want it done & settled out. I prefer to minimalize how much gets pitched beyond the yeasties themselves. I don't like adding to volume so as to maintain as much consistency as possible in regard to the recipe. Boy,that damn bluejay is a loud squawker ever since he took over the pin oak out front. Derails my train of thought & sleep with that loud raven like raspy squawk.
And to convert those big "little" starters you guys are dumping in plain unhopped beer & all- 2L equals .528 gallons! So 1L = .264 Gallons. So in a 5 gallon batch,that 2L starter has just made it a shade over 5.5 gallons. The formula to convert Liters to Gallons is L x .264 = G. From Science Made Simnple/Conversion Formulas...

 

[Paul_Aris]

After refridgerated and decanted do you let the starter warm up room temp or at least 65 before pitching? I used to do starters but stopped after trying US 05 dry yeast for IPAs and having great results. Everyone says to make sure you pitch the proper amount of yeast. But wouldnt one pack of dry yeast or 1 vial of white labs or wyeast be the proper amount for 5 gallons? So why take the time to do a starter at all?

 

[unionrdr]

After refridgerated and decanted do you let the starter warm up room temp or at least 65 before pitching? I used to do starters but stopped after trying US 05 dry yeast for IPAs and having great results. Everyone says to make sure you pitch the proper amount of yeast. But wouldnt one pack of dry yeast or 1 vial of white labs or wyeast be the proper amount for 5 gallons? So why take the time to do a starter at all?

You let it warm up to room temp while brewing,etc. Or at least to within 10 degrees of what the wort temp will be at pitching time to keep from shocking the yeast. I've pitched 1 White Labs vial before directly,& it took some 12 hours to get going,about the same as dry yeast just sprinkled on. Other times you need a starter to at least get close to the proper pitch rate.

 

[Paul_Aris]

You let it warm up to room temp while brewing,etc. Or at least to within 10 degrees of what the wort temp will be at pitching time to keep from shocking the yeast. I've pitched 1 White Labs vial before directly,& it took some 12 hours to get going,about the same as dry yeast just sprinkled on. Other times you need a starter to at least get close to the proper pitch rate.

I am asking to see what the benefits vs the cost of time is. Is it not more important to hit your FG than how long it takes for fermentation to start. I would think start would be a hard number to know if in a sealed vessel with X amount of headbspace. In other words the headspace would have to completely fill up with pressure before you see much airlock activity. Doesnt mean fermentation has not started.

 

[two_hearted]

I am asking to see what the benefits vs the cost of time is. Is it not more important to hit your FG than how long it takes for fermentation to start. I would think start would be a hard number to know if in a sealed vessel with X amount of headbspace. In other words the headspace would have to completely fill up with pressure before you see much airlock activity. Doesnt mean fermentation has not started.

The important thing is to pitch the right amount of healthy, active yeast for your wort. 1 packet of dry yeast (rehydrated) is enough cells for a 5 gal batch up to about 1.060 or so. Higher than that and you'll need more cells. 1 tube of white labs yeast has about 70-120 billion cells. A 5 gallon batch of 1.048 needs about 180 billion cells. So, you either need two tubes, or a starter to build up the cell count.

There is benefit to waking up all of those yeast cells to get ready for fermentation. So, I would rather make a starter with 1 tube to get my cell count and getting them moving. They will be healthier, there will be less lag time, the yeast will be less stressed which all lowers your chances for off flavors and other issues.

I have great results with just rehydrating dry yeast and pitching it too.

Great info here on pitching rates: http://www.mrmalty.com/pitching.php
great way to figure out how much yeast is needed here: http://www.mrmalty.com/calc/calc.html

 

[ktblunden]

I am asking to see what the benefits vs the cost of time is. Is it not more important to hit your FG than how long it takes for fermentation to start. I would think start would be a hard number to know if in a sealed vessel with X amount of headbspace. In other words the headspace would have to completely fill up with pressure before you see much airlock activity. Doesnt mean fermentation has not started.

The longer the lag time, the more opportunity there is for bacteria and wild yeasts to make themselves at home. So really, they're both important to a point, but I haven't noticed that much difference between the lag time in pitching the full amount vs chilling, decanting, warming, and pitching. Like others I pitch the full starter if it's a small amount and decant if I'm making a big starter.

 

[Denny]

Exactly. That's what everyone seems to be doing...but if it is a 1/2 pint starter, the liquid wont really affect the overall taste of the final beer and you can pitch yeast cells that are actively eating sugar away. Why would anyone want them go dormant in the fridge? This is what puzzles me.

By the way....thanks for the reply.

A 1/2 pint starter is worse than no starter at all. There's not enough food there for the yeast to rebuild their glycogen reserves before you pitch it, so it goes into the wort in a nutrient deficient state.

You want the yeast to go dormant in the fridge precisely because you don't want them consuming those nutrients before you pitch the yeast into the wort.

 

[Denny]

I just saw your reply to union, and (as I'm sure you know this) you don't pitch the yeast right out of the fridge. You have to let it warm up naturally to room temp first. Also, putting them back in suspension rouses the yeast from their dormancy, especially in room temp liquid.

Not so. For many years and hundreds of batches I've been pitching starters directly out of the fridge. By doing that, you keep the yeast from consuming their nutrients before they get into the wort. Try it, it works great.

 

[progmac]

^ That man knows a thing or two.

...i just yesterday pitched two decanted starters straight out of the fridge into a split lager batch. fermentation signs within 8 hours and krausen within about 20. and this is a lager at 52 degrees.

 

[Demus]

Exactly. That's what everyone seems to be doing...but if it is a 1/2 pint starter, the liquid wont really affect the overall taste of the final beer and you can pitch yeast cells that are actively eating sugar away. Why would anyone want them go dormant in the fridge? This is what puzzles me.

By the way....thanks for the reply.

I think you're missing the point of a starter. You are trying to achieve a certain cell count/pitch rate, not necessarily pitch actively fermenting yeast. There can be advantages to pitching an active starter, but the biggest disadvantage I can see is if you don't let it completely ferment out, you won't have achieved the cell count you were after. Make sense?

 

[zacster]

I've pitched my last 3 batches straight off the stir plate without decanting and all 3 brews took off like gangbusters and finished drier than I expected. 2 of them were higher gravity IPAs of around 1.075, and the third was a saison at 1.050. The second IPA finished at 1.012 after 4 days using Wyeast 1056! I never had fermentation like that. (and the added alcohol gave it an added kick.)

I make 2 liter starters using a stir plate and extra light dme, and my batches are all-grain BIAB. Do I mind adding extract to an otherwise all-grain batch? Nah. The results are what matter and I've gotten great results lately. I stopped decanting mostly because each of these last batches were hurry-up affairs, based on the rainy weather forecast, but now I'm going to stick to this method even if I have time. Lagers will be different, I'll probably decant those.

 

[unionrdr]

Not so. For many years and hundreds of batches I've been pitching starters directly out of the fridge. By doing that, you keep the yeast from consuming their nutrients before they get into the wort. Try it, it works great.

What temp was the wort vs the yeast starter temp? Were they within 10 degrees of eachother as is common? I have an infrared thermometer to very quickly check these with now.

I've pitched my last 3 batches straight off the stir plate without decanting and all 3 brews took off like gangbusters and finished drier than I expected. 2 of them were higher gravity IPAs of around 1.075, and the third was a saison at 1.050. The second IPA finished at 1.012 after 4 days using Wyeast 1056! I never had fermentation like that. (and the added alcohol gave it an added kick.)

I make 2 liter starters using a stir plate and extra light dme, and my batches are all-grain BIAB. Do I mind adding extract to an otherwise all-grain batch? Nah. The results are what matter and I've gotten great results lately. I stopped decanting mostly because each of these last batches were hurry-up affairs, based on the rainy weather forecast, but now I'm going to stick to this method even if I have time. Lagers will be different, I'll probably decant those.

Well,2L equaling .528 gallons,don't you think that's a bit much to pitch into 5 gallons? Are you accounting for the greater added volume? 1/2 gallon plus is a lot of extra starter liquid to be adding to a recipe volume imo.

 

[chickens4life]

In my mind there are to reasons to use starters: 1 is to get proper pitching rates with out having to buy multiple vials of yeast, 2 is to generate the healthiest yeast possible, to reduce yeast stress and the resulting off flavors and risk of autolysis.

pitching a still fermenting start is fine for the first goal, as long as you make a slightly larger volume to account the cells not being done dividing. but for the second goal you want the yeast to have fermented out the starter and built up some glycogen reserves. which likely will not have happened if you pitch a fermenting starter.

yeast don't go into some hibernation state in the fridge that is going to take them hours to come out of, if you decant a starter and let it warm on the counter while you are cleaning up and pitch it as soon as it gets reasonably close to the wort temp it will take very little time for visible signs of fermentation to show.

if you don't care about having your starter beer change the volume or ad yeast character to your batch there is really no compelling reason to decant, you just want to let the starter ferment out before using it so that the yeast can build up some glycogen stores. I ferment starters at room temp which is normally quite high here, so I decant all of them, the starter beer has some nasty ester/ phenolic notes that I don't really want in my beer.

just my two cents

chickens

 

[Denny]

What temp was the wort vs the yeast starter temp? Were they within 10 degrees of eachother as is common? I have an infrared thermometer to very quickly check these with now.

Wort about 60-65F, yeast out of fridge at maybe 45F.

 

[unionrdr]

Well said chickens! I ferment starters at room temp as well. so I pour off most of the starter liquid,saving enough to swirl up the yeast with. And with my infrared thermometer,checking wort/starter temps will be a lot faster & more accurate.
@ Denny-Hmmm...lower by by about 20 degrees. I had my fridge programmed for 47F,have to check that. I typically get my wort chilled to about 65F. You haven't observed/smelled/tasted anything during the process to indicate off flavors,or some other fault as a result of being some 20 degrees lower than wort temp? Like length of reproductive phase? Vigor of initial fermentation?

 

[Elysium]

A 1/2 pint starter is worse than no starter at all. There's not enough food there for the yeast to rebuild their glycogen reserves before you pitch it, so it goes into the wort in a nutrient deficient state.

You want the yeast to go dormant in the fridge precisely because you don't want them consuming those nutrients before you pitch the yeast into the wort.

http://www.wyeastlab.com/com-yeast-storage.cfm <--- I have just found this info on glycogen.

I understand what you mean.....that in a small amount of wort the yeast wont be able to revive and have a healthy starting point for its life-cycle.

By the way....I am making 1 uk pint starters....if I said 1/2 pint before in any of my messages...then I am sorry, it was a mistake.

 

[Elysium]

The biggest disadvantage I can see is if you don't let it completely ferment out, you won't have achieved the cell count you were after. Make sense?

Hey Demus,

Thanks for the reply. The cellcount will depend on how much yeast I put in the starter and how big my starter is. Is that what you are trying to refer to?

I actually dont understand the line I quoted from your previous post. Can you explain that to me in details? Thanks.

 

[Elysium]

For the second goal you want the yeast to have fermented out the starter and built up some glycogen reserves. which likely will not have happened if you pitch a fermenting starter.

Hey. Very interesting thoughts. Can you give me more information on the line I quoted from you?

When exactly does this stage set in? I mean when exactly does the yeast ferment out the starter and build up those glycogen reserves?

I am actually making 1.030 starters of 1 UK pint using MO malt.

 

[unionrdr]

When it starts to settle out & no more swirling,etc kind of activity is seen i would think. That's basically what I go by. but then again,I don't have a stir plate.

 

[Denny]

http://www.wyeastlab.com/com-yeast-storage.cfm <--- I have just found this info on glycogen.

I understand what you mean.....that in a small amount of wort the yeast wont be able to revive and have a healthy starting point for its life-cycle.

By the way....I am making 1 uk pint starters....if I said 1/2 pint before in any of my messages...then I am sorry, it was a mistake.

There is also this from mrmalty.com...

"Q: I've heard that too small or too large a starter can be bad for the yeast. How is that possible?

(Neva) Parker (from White Labs) says putting a fresh vial of yeast into 500 ml of wort and letting such a small starter go to completion can actually leave the yeast less ready to ferment a batch of beer. The yeast do not rebuild their reserves and have very little increase in cell mass.

The minimum starter size for significant yeast growth from a vial or pack of yeast is 1 liter. One vial or pack into 1 liter results in approximately a 50% increase in cell mass. "

 

[unionrdr]

Good quote. So my 1L (1000mL) flask is the right size to git-r-done for the average ale then.

 

[ShootsNRoots]

Cold Pitching works well for me.

http://www.brewboard.com/index.php?showtopic=26969

http://forum.northernbrewer.com/viewtopic.php?f=26&t=70971
http://forum.northernbrewer.com/viewtopic.php?f=1&t=652

 

[Denny]

Good quote. So my 1L (1000mL) flask is the right size to git-r-done for the average ale then.

I'd say you need a flask bigger than 1L to make a 1L starter. I use a gal. glass jug.

 

[unionrdr]

1000Ml does come up close to the neck. I'll try it anyway,since it's all I have to make starters for my washed yeasts. Might need a mini blow off though...

 

[Demus]

Hey Demus,

Thanks for the reply. The cellcount will depend on how much yeast I put in the starter and how big my starter is. Is that what you are trying to refer to?

I actually dont understand the line I quoted from your previous post. Can you explain that to me in details? Thanks.

No sweat. Maybe the word starter is misleading. It makes it sound like the purpose is to "wake up" the yeast. There's no requirement or benefit that I know of (under normal conditions) to pitching actively fermenting yeast. It will still stop, absorb oxygen and have a lag phase. The purpose is to propagate the yeast sample up to the recommended cell count for your batch. By interrupting your starter, you are not allowing it to get to that cell count. Of course it still works, because yeast are very resilient and adaptable organisms. But the flavor could be less than ideal, as the impact of under pitching is pretty well documented.
All that said, for a stalled ferment or a huge alcohol beer pitching yeast at high kruesen can be an effective technique to get those last stubborn points of attenuation...

 

[zacster]

Well,2L equaling .528 gallons,don't you think that's a bit much to pitch into 5 gallons? Are you accounting for the greater added volume? 1/2 gallon plus is a lot of extra starter liquid to be adding to a recipe volume imo.

I start boiling my starter with 2 liters, by the time it's done it's more like 1600ml. And still, the primary brew recipe remains the same, same hop schedule, same grain bill, and that's the critical part. Adding another 1/3 gallon to it won't change the character as you are adding wort, not water or anything else.

Let's say I wanted to match the brew with the starter (something I used to do by default as I would use the LME from my kits, but then decant). If I used 5 oz of hops, a large amount, I would need to add another 1/3 oz? That's a small handful of pellets. I don't measure anything in those increments anyway.

One thing I've always said on the forums: No matter what you do, you will always end up with beer. It may not be the exact taste you were looking for, but it will be beer. In my recent cases, it was better than anything I've ever expected. Even the LHBS guys were impressed.