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Is quick cooling of yeast starter wort necessary?

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TaoBrewer

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Awesome site, been reading for weeks and just joined. Done 4 batches and did my first yeast starter on an IPA I cooked yesterday.

My question is, is there any meaningful practical value to quickly cooling (ice water, fridge, etc.) the yeast starter wort after the 15-20 minute boil? I'm talking about a 2 liter amount used with a Wyeast smack pack. Reason I ask, is if no need for rapid cool down, I can quickly pressure cook the wort and have total sterility. Thanks for any help.
 
I just cool down starter worts in reasonable time, all you are concerned with is growing yeast and not getting an infection. Usually the yeast is going in once the temp is 70 in my process.
 
Awesome site, been reading for weeks and just joined. Done 4 batches and did my first yeast starter on an IPA I cooked yesterday.

My question is, is there any meaningful practical value to quickly cooling (ice water, fridge, etc.) the yeast starter wort after the 15-20 minute boil? I'm talking about a 2 liter amount used with a Wyeast smack pack. Reason I ask, is if no need for rapid cool down, I can quickly pressure cook the wort and have total sterility. Thanks for any help.

No need to boil for that long. 1 minute sanitizes. That (and mixing everything nicely) is the purpose of bring things to a boil.

No need for a rapid cooling.

Cool it in a reasonable time frame. I'm not going to waste ice on it. I let it cool as I do other things and cool it by putting it in a sink of water. Cold break is not important in a starter.
 
No need to boil for that long. 1 minute sanitizes. That (and mixing everything nicely) is the purpose of bring things to a boil.

No need for a rapid cooling.

Cool it in a reasonable time frame. I'm not going to waste ice on it. I let it cool as I do other things and cool it by putting it in a sink of water. Cold break is not important in a starter.

Thanks! That's what I was hoping for.
 
No worries. For more info, there is a link on starters in my sig below

Thanks ... great link. Maybe you know the answer to this. Let's say I start with a Wyeast smack pack that has 100 billion yeast cells in it. If I was to pour that yeast pack EQUALLY into three separate 2 liter jars of perfectly prepared starter wort, would I get more yeast cells for pitching (maybe 3 different batches of beer) than if I put the whole pack into one 2 liter jar?

I'm trying to figure out how to turn 1 smack pack into 3-4 starters that each have 250 - 300 billion cells in them ...
 
Thanks ... great link. Maybe you know the answer to this. Let's say I start with a Wyeast smack pack that has 100 billion yeast cells in it. If I was to pour that yeast pack EQUALLY into three separate 2 liter jars of perfectly prepared starter wort, would I get more yeast cells for pitching (maybe 3 different batches of beer) than if I put the whole pack into one 2 liter jar?

I'm trying to figure out how to turn 1 smack pack into 3-4 starters that each have 250 - 300 billion cells in them ...

yes. You get more yeast as your effectively making a 6L starter.

If your planning on doing 3 beers at once and the demands of the 3 dictate the need for a big starter like that it's a decent plan.

If your planning staggered brewdays a better way is to overbuild a starter and save some for the next batch (like I show in the article)

You can get pretty much never ending yeast this way. I do it every time saving 100B yeast for next time.

2 things that make this easier are a big flask (5L) and a DIY stir-plate (starters need not be as large to target a certain pitch rate).

Another option is to save the yeast slurry from the first brew in sanitized jars. You get more yeast than you can use this way. There are pros/cons to each approach.

Slurry saved in mason jars.
DSC02249.jpg

Yeast ranching/harvesting/overbuilding is fun and a great way to keep a variety of yeast on hand. It also saves you $$

My last brew I used overbuilt yeast saved yeast from a starter I made in July.

2.5L starter made, saved ~100B and used the rest (after decanting off the unwanted starter beer) on the batch I made. Works like a champ.
 
yes. You get more yeast as your effectively making a 6L starter.

If your planning on doing 3 beers at once and the demands of the 3 dictate the need for a big starter like that it's a decent plan.

If your planning staggered brewdays a better way is to overbuild a starter and save some for the next batch (like I show in the article)

You can get pretty much never ending yeast this way. I do it every time saving 100B yeast for next time.

2 things that make this easier are a big flask (5L) and a DIY stir-plate (starters need not be as large to target a certain pitch rate).

Another option is to save the yeast slurry from the first brew in sanitized jars. You get more yeast than you can use this way. There are pros/cons to each approach.

Slurry saved in mason jars.
View attachment 327865

Yeast ranching/harvesting/overbuilding is fun and a great way to keep a variety of yeast on hand. It also saves you $$

My last brew I used overbuilt yeast saved yeast from a starter I made in July.

2.5L starter made, saved ~100B and used the rest (after decanting off the unwanted starter beer) on the batch I made. Works like a champ.

GREAT info!!! So, if I'm understanding you correctly, it's not necessarily how many cells you start with in the new starter, it's how much liquid starter wort you use, right? If I put 30 billion yeast cells into a starter wart of 3 liters I'll get 3x as much new yeast cells as if I put those 30 billion cells into only 1 liter?
 
If you want to cool it quickly, one way is to do a concentrated boil on the starter wort, chill that, and then add clean water to it (maybe you boiled it a day before and let it cool in a sterile container for a day, or you could add bottled water if you trust it). The concentrated wort cools faster because of the smaller volume. You can also chill the make-up water to drop the temp quickly.
 
GREAT info!!! So, if I'm understanding you correctly, it's not necessarily how many cells you start with in the new starter, it's how much liquid starter wort you use, right? If I put 30 billion yeast cells into a starter wart of 3 liters I'll get 3x as much new yeast cells as if I put those 30 billion cells into only 1 liter?

It's not the volume that dictaes growth it's the mass of DME used.

Having said that, you want a SG of 1.037-1.040 for a starter to optimize growth /gram of DME.

If all starters are in thes SG range then yes, starter volume is the variable in play.

To a point. You also don't want to massively under pitch a starter.

eg: (1B yeast in a 3L starter is not a good plan in all likelihood)

There is a golidilocks zone for getting best growth while minimizing yeast stress. Two goals in making a starter.
 
It's not the volume that dictaes growth it's the mass of DME used.

Having said that, you want a SG of 1.037-1.040 for a starter to optimize growth /gram of DME.

If all starters are in thes SG range then yes, starter volume is the variable in play.

To a point. You also don't want to massively under pitch a starter.

eg: (1B yeast in a 3L starter is not a good plan in all likelihood)

There is a golidilocks zone for getting best growth while minimizing yeast stress. Two goals in making a starter.

What would you guess is the approximate minimum number of yeast cells to pitch to a 2 liter starter wort with perfect SG to get to >200 billion when finished? This would assumbe using optimal stir plate system?
 
not necessary, but i like to cool it down as fast as possible, just so i can get the starter going, and be done with it. Whats a few pieces of ice out of the freezer in a sink of water? I just like to be done with it so i can get onto other things. And for smaller beers, i do a starter the morning i brew. The faster i get done with the starter, the sooner i get out to the brew room to start brewing
 
What would you guess is the approximate minimum number of yeast cells to pitch to a 2 liter starter wort with perfect SG to get to >200 billion when finished? This would assumbe using optimal stir plate system?

To be honest I've no idea

here is a good calculator to play around with though. Might help you answer that.

http://www.brewunited.com/yeast_calculator.php

To give the example of my most recent starter, made last Monday for a Friday brew.
  • 100B yeast harvested in mason jars.
  • Projected viability was 35% =35B total after 6 months of storage in the fridge.
  • 2.5L starter gave me enough for my 5.5 gallon hybrid pitch rate in a wort of 1.049 with enough for a 100B harvest for future brews.

This was a less than optimal pitch rate for this starter but no problems resulted.

Here is the fermenting beer 24hours after pitching (6 month old yeast, fresh starter, fermenting beer is controlled @ 58F)

attachment.php


Point being the calculators are approximations. Not hard and fast yes/no rules.

Also the Braukaiser has done great work on studying a variety of things including starters.

A trove of information to be found here.
 
yes. You get more yeast as your effectively making a 6L starter.

If your planning on doing 3 beers at once and the demands of the 3 dictate the need for a big starter like that it's a decent plan.

If your planning staggered brewdays a better way is to overbuild a starter and save some for the next batch (like I show in the article)

You can get pretty much never ending yeast this way. I do it every time saving 100B yeast for next time.

2 things that make this easier are a big flask (5L) and a DIY stir-plate (starters need not be as large to target a certain pitch rate).

Another option is to save the yeast slurry from the first brew in sanitized jars. You get more yeast than you can use this way. There are pros/cons to each approach.

Slurry saved in mason jars.
View attachment 327865

Yeast ranching/harvesting/overbuilding is fun and a great way to keep a variety of yeast on hand. It also saves you $$

My last brew I used overbuilt yeast saved yeast from a starter I made in July.

2.5L starter made, saved ~100B and used the rest (after decanting off the unwanted starter beer) on the batch I made. Works like a champ.

These pictures look like 1/2 pint Mason Jars nearly filled with slurry. How many cells of usable yeast do you estimate is in each jar? If I compare this to, let's say 3 smack packs of Yeast, this seems like A LOT, LOT more in that 1/2 pint? Is that correct?

Or is a lot of the slurry not really usable yeast?
 
These pictures look like 1/2 pint Mason Jars nearly filled with slurry. How many cells of usable yeast do you estimate is in each jar? If I compare this to, let's say 3 smack packs of Yeast, this seems like A LOT, LOT more in that 1/2 pint? Is that correct?

Or is a lot of the slurry not really usable yeast?

Yes 1/2 pint jars

Filled to the very brim with slurry. It settles over time. This is 1 day post harvest.

How many cells?
Wide ranges exist in the various calculators. 1 half pint jar of fresh slurry was ample (probably a major over-pitch) for a 1.054 stout brewed 1 day after harvest. No fermentation issues.

3 packs of liquid yeast if straight off the production line would probably contain a similar yeast count to what is in one 1/2 pint of freshly harvested slurry. Cost is substantially more though. $24 -v- $0

I no longer harvest yeast in this manner. I favor a handier and I would argue more useful method for keeping an endless and almost cost-free supply of yeast on hand.
 
When you say filled to the brim...You literally mean all the way up? Or do you stop 1/4 inch from the top or so?

I like this idea and am planning to implement with my next starter.
 
I no longer harvest yeast in this manner. I favor a handier and I would argue more useful method for keeping and endless and almost cost-free supply of yeast on hand.

??? What is it? (thanks for your advice, BTW!)
 
No worries Tao

This link describes what I do

https://www.homebrewtalk.com/showthread.php?t=532452

FANTASTIC THREAD!!!! Just what I needed.

In the pictures, you have your big flask and two pint sized mason jars. Do you dilute your original yeast into that measuring cup and then pour some into the pint mason jars and the rest into the big flask? Trying to understand exactly how you get the small mason jars up and running ... is it all done at the same time or are your using some of the starter wort from the big flask to fill up the small mason jars AFTER the big flask has fermented first?

Sorry for all the question, but this is exactly the issue I'm trying to get clear in my head now.
 
FANTASTIC THREAD!!!! Just what I needed.

In the pictures, you have your big flask and two pint sized mason jars. Do you dilute your original yeast into that measuring cup and then pour some into the pint mason jars and the rest into the big flask? Trying to understand exactly how you get the small mason jars up and running ... is it all done at the same time or are your using some of the starter wort from the big flask to fill up the small mason jars AFTER the big flask has fermented first?

Sorry for all the question, but this is exactly the issue I'm trying to get clear in my head now.

Ferment starter to completion.

Pour preplanned overbuild volume into the previously sanitized jars. Do this immediately after taking the starter off the stir plate when everything is homogenous.

Cap the jars loosely and place in fridge. Label them

After a day or two cinch the lids tight

The remaining majority flask held volume of the starter is put in the fridge also. Chill for a day or three.

Prior to pitching the yeast remove it from the fridge, pour off the nasty starter beer leaving just enough to swirl up the yeast cake. (200ml is all that's usually needed but a bit more is no problem)

Allow the yeast to warm closer to your pitching temperature. For me pitching temp ranges from 48 to 62F. I do not measure the yeast temp. I just let it warm a bit for an hour or so.

Pitch yeast.

Here is a good write up by @Brulosopher
 
Ferment starter to completion.

Pour preplanned overbuild volume into the previously sanitized jars. Do this immediately after taking the starter off the stir plate when everything is homogenous.

Cap the jars loosely and place in fridge. Label them

After a day or two cinch the lids tight

The remaining majority flask held volume of the starter is put in the fridge also. Chill for a day or three.

Prior to pitching the yeast remove it from the fridge, pour off the nasty starter beer leaving just enough to swirl up the yeast cake. (200ml is all that's usually needed but a bit more is no problem)

Allow the yeast to warm closer to your pitching temperature. For me pitching temp ranges from 48 to 62F. I do not measure the yeast temp. I just let it warm a bit for an hour or so.

Pitch yeast.

Here is a good write up by @Brulosopher

Exactly what I was looking for. This system makes a lot of sense and seems very unlikely to contaminate over time. Thanks again!

BTW, using your advice, I brewed my best batch a few weeks ago, an IPA that came in at 7.2 ABV and had absolutely EXPLOSIVE fermentation within hours of getting started. Fermented down from 1.060 to 1.011 so the yeast element of the equation was perfect as it was the first time I used a starter. Flavor is amazing!
 
Exactly what I was looking for. This system makes a lot of sense and seems very unlikely to contaminate over time. Thanks again!

BTW, using your advice, I brewed my best batch a few weeks ago, an IPA that came in at 7.2 ABV and had absolutely EXPLOSIVE fermentation within hours of getting started. Fermented down from 1.060 to 1.011 so the yeast element of the equation was perfect as it was the first time I used a starter. Flavor is amazing!

Glad to hear that. Sounds like a great result.
 
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