Basics Of Making And Using A Yeast Starter

[Killer Brew]

*bump*

Any advice for me on this one? Thanks.

 

[Mardoo]

Duplicate post

 

[Mardoo]

Ideally let the yeast drop and drain off. Almost all growth is finished by 24 hours. This would be my process with the volumes you mention, based on the information in the Yeast book by White and Zainisheff:

Yeast into 1l wort with yeast nutrient
Stirplate 24hours
Rest at room temp 24 hours (builds glycogen reserves)
Refrigerate 24 hours (builds trehalose reserves)
Decant wort.
Add yeast to 3l wort with yeast nutrient
Stirplate 24 hours
Rest at room temp 24 hours (builds glycogen reserves)
Refrigerate 24-48 hours (builds trehalose reserves)
Decant wort
Allow to warm slowly to pitching temp
Pitch

Boil the nutrient with the wort when you prep it, of course.

 

[Brew Forky]

Yesterday I divided a smack pack into 3 x 1L starters. I'm only using one starter and plan on restarting the others at a later date. But it's got me thinking, would the yeast produced in 3 x 1 L equal the yeast produced in a 3 L starter? I reckon it would or am I missing some yeast propagation mathematics here? In relation to the above posts, in my very amateur opinion it would be easier than stepping it up.

 

[mofox1]

One note on the refrigeration step - make sure the starter has finished fermenting the sugars before you bung it in the fridge. If there are still bubbles appearing (at rest - not when agitated) then the yeast are still actively chomping through the sugar and wont drop well when chilled.

Been mentioned previously, but two things will help with a nice quick ferment - warm temps and a low OG. Temp for good yeast starters are above that for beer fermentation, room temp is okay but a little warmer (ie 21-25C) will ferment out quickly. Keep the OG of the start low - around 1.030 is good, don't go over 1.040.

The starter should change colour from a sort of transparent browny/yellow to an opaque creamy yellow, if it hasn't changed colour then the yeast haven't kicked off yet.

I've noticed the initial kickoff is taking longer at the moment, likely due to the arctic conditions in the house overnight thanks to sub standard insulation. I've been warming the flask in the sink with ~28C water for 30mins or so in the morning to help it along before the house temp is habitable. So those 24hrs on the stir plate may be around 48hrs if you're in melbs.

 

[goatchop41]

Just a quick couple of questions on "stepping up" that I couldn't see the answer for here.

I need 4 times the cell count as provided by my liquid yeast. Looks like I need a big starter, at least 3L. I have made a 1L starter so far. To step up to the 2L starter do you (a) add a further 1L of wort; or b siphon off the initial wort and add 2L of fresh wort? Also what is the timing of the step up (ie. fully fermented or earlier)? Thanks.

It depends on how big your starter vessel is...if the second step is 2L, then you either have to cold crash-->decant-->add 2L of new wort OR keep the 1L-->add 2L of new wort. Either works.

Also, have a look at the yeast starter calculator at http://www.homebrewdad.com/yeast_calculator.php - it will tell you exactly how many steps you need and what size, and you can change the strength of your starter wort in the calculator as you see fit.....one thing though, I've noticed that it doesn't seem to work properly if you change the settings on the batch size units from gallons to litres - it still gives all of the rest of the figures as if you were inputting gallons (eg enter 5L and it gives you the yeast figures for 5gal) so just input your batch size as gallons :beerbang:

 

[Coodgee]

So I followed the instructions in the original post this morning when making a starter of some WY2112. My "1L" conical flask is probably not that great for making a 1L starter because there is not much room in the top to shake it up and get some air into the wort. I'll just resume periodic shaking as best I can when I get home from work I spose.

 

[dannymars]

I'm having trouble growing enough yeast for a lager...

I have 2 x 1Lt erlenmeyer flasks and 1 x 2lt erlenmeyer flask

Mrmalty (and other calcs) say I need a 3 stage step-up for my one vial of WLP800

I made a 2 ltr starter on Wednesday... put it on the stir plate, kept it at 20C.

Got home last night, seemed to be going ok, krausen happening etc... I put the starter in the fridge to try and cold crash/stop fermenation.... as Lager yeast likes the cold, it just kept fermenting, even more vigorously.. turned fridge down to 1C and left it over night...

got up this morning and the yeast hadn't really yet settled out, bubbles still rising etc... but I decanted and re-pitched into another 2 ltrs of wort anyway.

Didn't seem to be that much slurry, did I decant too soon? how the **** do you easily get enough yeast to pitch into 40ltrs of lager? multiple vials?... I thought my 2ltr flask and stir plate would do it... but even if all went well, it's still a stretch... most calcs recommending massive starters of 5+ ltrs.... :-/

 

[gap]

try a 5 litre flask

 

[danestead]

I'm having trouble growing enough yeast for a lager...

I have 2 x 1Lt erlenmeyer flasks and 1 x 2lt erlenmeyer flask

Mrmalty (and other calcs) say I need a 3 stage step-up for my one vial of WLP800

I made a 2 ltr starter on Wednesday... put it on the stir plate, kept it at 20C.

Got home last night, seemed to be going ok, krausen happening etc... I put the starter in the fridge to try and cold crash/stop fermenation.... as Lager yeast likes the cold, it just kept fermenting, even more vigorously.. turned fridge down to 1C and left it over night...

got up this morning and the yeast hadn't really yet settled out, bubbles still rising etc... but I decanted and re-pitched into another 2 ltrs of wort anyway.

Didn't seem to be that much slurry, did I decant too soon? how the **** do you easily get enough yeast to pitch into 40ltrs of lager? multiple vials?... I thought my 2ltr flask and stir plate would do it... but even if all went well, it's still a stretch... most calcs recommending massive starters of 5+ ltrs.... :-/

Yep as above, 5L flask. In fact, I use my 5L flask very often and I only brew 21L batches. I also have a 2L flask so if I'm doing a 2 step starter is is very easy to decant from the 2L flask and then into the 5L flask.

Why were you trying to stop the fermentation of the starter?

 

[dannymars]

Yep as above, 5L flask. In fact, I use my 5L flask very often and I only brew 21L batches. I also have a 2L flask so if I'm doing a 2 step starter is is very easy to decant from the 2L flask and then into the 5L flask.

Why were you trying to stop the fermentation of the starter?

yep, I know a bigger flask will work... Just seems like a shitload of starter (10-25% or total wort volume!).. Plus I don't have a 5ltr flask.

I was trying to stop fermtation for a number of reasons... 1. I was under the impression that it's just the growth phase that mattered, not the fermentation. Also, in order to get 3 step-ups by the weekend I'm pressed for time.

Dunno what to do now :-/

 

[goatchop41]

yep, I know a bigger flask will work... Just seems like a shitload of starter (10-25% or total wort volume!).. Plus I don't have a 5ltr flask.

I was trying to stop fermtation for a number of reasons... 1. I was under the impression that it's just the growth phase that mattered, not the fermentation. Also, in order to get 3 step-ups by the weekend I'm pressed for time.

Dunno what to do now :-/

Building a proper pitch for lagers needs proper planning for timing, and a big flask. A cold crash of 24 hours would have settled it much better.....No suggestions fr how you can get it ready for the weekend though, I think that you've cut it a bit too fine for time!!

 

[danestead]

yep, I know a bigger flask will work... Just seems like a shitload of starter (10-25% or total wort volume!).. Plus I don't have a 5ltr flask.

I was trying to stop fermtation for a number of reasons... 1. I was under the impression that it's just the growth phase that mattered, not the fermentation. Also, in order to get 3 step-ups by the weekend I'm pressed for time.

Dunno what to do now :-/

Yep, lagers do generally require a large starter depending on how much yeast you start with. The cost of DME sure adds up when you are making 5L of starter because that stuff isn't cheap.

I think I'm fairly educated in yeast starters as I've read quite a lot about them however I've never heard of anything regarding stopping the ferment after the growth phase. You are correct in saying that the starter is primarily for yeast growth however the only techniques I've read about are either pitching the whole starter volume into you fermenter at the peak of yeast activity after most of the growth phase is complete or #2 to let the starter completely ferment out, let the yeast flocculate and then decant the beer off the top of the yeast and pitch the remaining yeast layer.

My GUESS is that chilling your starter after you think the growth phase is complete is not all that great for yeast health.

 

[danestead]

As for getting it ready for the weekend, are you able to get to a home brew shop to buy more yeast? Do you have any dry lager yeast you can use or buy? Is there any home brewers near you that can give you some yeast?

What is your calculated quantity of yeast thus far? Is it far off the amount you are trying to grow? Although not ideal, you could just pitch what you have.

Actually, thinking of that, I read an article saying you can pitch a smaller number of yeast but at a higher temperature, then after a couple of days (the end of the growth phase) you can bring the temperature down to your normal lager fermenting temp (not too fast, no more than about 4 degrees per day). Not sure if you have temp control but it's an option however it's not something I would try because I think it would create a large amount of diacetyl but I'm just saying that I did read an article regarding that.

 

[dannymars]

pack viability is guessed @ 70% = 70 billion cells...

amount needed for a 1.048 lager @ 40ltrs is 715 billion cells!! calculated that I could get there with 3 steps of a 2 ltr starter.... 1 day per step is what I planned... but looks like it's gonna take a lot longer than that.... 1 step recommended an 8ltr starter, which seems ridiculous to me... but hey :-/

blimey, reckon I'd be at 150 billion if I was lucky.

 

[danestead]

pack viability is guessed @ 70% = 70 billion cells...

amount needed for a 1.048 lager @ 40ltrs is 715 billion cells!! calculated that I could get there with 3 steps of a 2 ltr starter.... 1 day per step is what I planned... but looks like it's gonna take a lot longer than that.... 1 step recommended an 8ltr starter, which seems ridiculous to me... but hey :-/

blimey, reckon I'd be at 150 billion if I was lucky.

Hmmmm.

Can you whack 2 packets of US05 in your beer and call it a faux lager?

 

[dannymars]

the shop near my house has saflager... maybe I'll grab a few packs of that...

liquid yeast for next time... (I can save the starter slurry I've already made in a mason jar for later)

 

[Black n Tan]

calculated that I could get there with 3 steps of a 2 ltr starter.... 1 day per step is what I planned...

Three steps of a 2L starter is not going to leave the yeast in good health. Typically each starter steps up in size, otherwise there is not enough nutrients for growth. The preferred ratio is 10x between steps, but that is not really practical at the home brew level so something more like 4x works. In your case you would have been better to make a 1L starter and then a 3 or 4L starter spread across 2 or 3 of your flasks. I allow at least 1 week for preparing a starter for a lager: 2 days on a stir plate for each step and at least 1 day cold crashing.

 

[Kingy]

You could always use the starter on half your 40 litre batch then after a few days add the other half to yhe allready fermenting beer. I love my 5 litre flask.

 

[Ditchnbeer]

Use Mr Malty to determine how many packets of dry yeast to use. 40 litre batch will need a fair amount & rehydrate them before pitching into your wort. The lesson here might be to plan ahead for a lager, so that enough healthy yeast is grown for the batch size. It might take a week or more to grow enough. Also Yeast react to changes in temp but with sudden changes (like in a cold crash) they can react in a way we don't want and can release off flavours. Same applies when the beer is finished - after diacetyl rest reduce temp by 1 degree per day until its ready to keg and lager. It takes more time but worth it. In my club the best brewers are all about the yeast.