Yeast Starter Question

[blainekehl]

I have a yeast starter question for the forum.
I made a starter with two packages of Wyeast 2278 Czech Pilsner Lager yeast and 2L of 1.036 wort on Sunday night.
This morning it appeared the fermentation was done. No bubbles, no krausen so I took it off the stir plate to let it settle out at room temperature.
Tonight I want to decant the beer off it and add another 2L of 1.036 wort on it.
I want to keep doing this until Saturday when I brew.
Do you think I’ll gain anything by doing this?
Theoretically I think I’ll keep building up yeast cells, but I would imagine there’s a point of diminishing returns.

Thanks!

 

[Kent88]

What kind of beer are you making? What OG are you shooting for? What is the target volume of the batch?

 

[blainekehl]

What kind of beer are you making? What OG are you shooting for? What is the target volume of the batch?

I'm making a Bohemian Pilsner, target OG 1.046, and target volume is 5.5 gallons.

 

[Kent88]

Wow, ok.

I don't have a Wyeast smack pack handy, but I'm pretty sure it says that one pack can sufficiently inoculate 5 gallons of 1.060 wort (unless it is after the "best before" date).

You're working harder than you need to. At this point, if I was in your shoes, I'd leave it alone until a few hours before I started brewing, and I'd only decant and add more starter just to wake the yeast back up.

 

[ba-brewer]

Depending on the age of your smack pack a single 2L starter may be all you need to do. In general the steps should be progressively larger or you can actually be causing the yeast to get stressed as there is not enough resources.

This is a decent yeast starter calculator. I like it as it will turns fields red that don't meet best practices.
http://www.brewunited.com/yeast_calculator.php

If I need multiple steps I adjust the size of the steps so the last step has a growth of two or more.

 

[blainekehl]

Thanks for your answers! I ended up stepping it up once more. When it's done I'm going to crash it and pour off the beer. Saturday morning when I start my brew I'll take it out of the fridge to let it warm up then pitch it.

 

[blainekehl]

Wow, ok.

I don't have a Wyeast smack pack handy, but I'm pretty sure it says that one pack can sufficiently inoculate 5 gallons of 1.060 wort (unless it is after the "best before" date).

You're working harder than you need to. At this point, if I was in your shoes, I'd leave it alone until a few hours before I started brewing, and I'd only decant and add more starter just to wake the yeast back up.

I probably am working harder than I need to. I just want to make sure I have lots of healthy yeast for this pilsner.

You said that you'd decant and add more starter to wake the yeast back up, when would you do that?

 

[Kent88]

I would try to have the starter wort cool and ready to add (after decanting) either

• about 2 hours before the start of the boil if you're making an extract batch, or
  
• after you measure out your strike water but before it reaches strike temperature (and definitely before you get the malt out of storage) if you are preforming a mash

At this point I wouldn't be looking to develop more yeast cells, there is already way more than needed, I'd want to just make sure that the cells were awake and ready to go when you add them to the chilled wort.

It is good that you're making sure that you have enough yeast, but it is possible to overdo it.

 

[ba-brewer]

Thanks for your answers! I ended up stepping it up once more. When it's done I'm going to crash it and pour off the beer. Saturday morning when I start my brew I'll take it out of the fridge to let it warm up then pitch it.

If you allow the yeast to warm to room temp then put into a chilled wort it will trigger them go back to sleep, sort of like cold crashing. It is better to pitch cold and allow the yeast to come up to temp in the wort. Most fridges are like mid 30 and you should pitch into a lager at 50F or below so there is less chance to shock yeast. Just chill your wort to 50 or below, decant the beer on top of the starter and pitch the yeast.

If you did your starter right and you had healthy yeast prior to putting in the fridge they will still be health a few days later.

 

[blainekehl]

The starter is crashing in my fermentation chamber at 1C/33F. Maybe I'll raise the temperature in the chamber to my pitching temperature of 12C/53F the night before I brew.