Stuck lager : re-pitching a starter - need calculation help/confirmation

[LitBrewing]

Hello fellow home brewers!
I am brewing 9 gallons german pilsner 1.53OG using 2 packages of WLP-800 (200b total cells) and I am almost certain I under-pitched. Zero activity even if I bring the temp up to 54 degrees ( from 50 ) after about 50 hours. I'm now looking at some calculators and they recommend more like 669 billion cells.

https://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/
So from here, since there are presumably 200b in the tank, I am thinking I need another 469 or so to get things moving.

When I first plug that into the calculator using the 'shaking' method and starting with another pack of 100b cells i would need a 9L starter?!?! That's a massive starter it seems, and 2 gallons would overflow my fermenter!
It looks like I might need to start with something like 3 more packs, and a 1.5 l starter, which is much more manageable.

Am I doing this correctly? Any other advice?
Thanks in advance

 

[Holden Caulfield]

You did under-pitch, but once it gets going, if you have good temperature control, you will make good beer. Raising the temperature beyond 54 could cause off flavors during growth phase so don't be tempted to raise the temp to get it going.

Also, in my experience with WLP800, it behaves differently than other yeast like 2124 (WLP830), 2206, 833, etc - it is incredibly slow to get going. Starters with fresh packs often take 24-36 hours just to get going, so if you make one it will be another couple days - unless you think your yeast was mishandled and not viable, you may want to just sit tight, things usually work out in the end.

 

[jdauria]

Yeah 200 billion cells is way too low for a 1.053 lager without a starter even if it was just a 5 gallon batch. if you do make another starter, just crash it in the fridge, then decant off most of the liquid and pitch just the yeast and enough remaining liquid to shake to get the stuck yeast off bottom of starter. If you are going to make lagers and large batches like that, I strongly suggest investing in an Oxygen wand and using pure O2 to oxygenate the beer instead of the shake method.

 

[LitBrewing]

Yeah I didn't really even shake the wort, I just transferred and lifted the transfer tube well above the level of the water/ferm vessel to create agitation.

*edit* found some good instructions for yeast starters. I do have a question though, if i'm using the same lager yeast should I grow the starter in the same ferm chamber in the low 50's?

 

[Beholder]

Yeah I didn't really even shake the wort, I just transferred and lifted the transfer tube well above the level of the water/ferm vessel to create agitation.

*edit* found some good instructions for yeast starters. I do have a question though, if i'm using the same lager yeast should I grow the starter in the same ferm chamber in the low 50's?

With the small volume of starter (especially if you decant), the risk of off flavors is nil, so I do starters room temperature both for ales and lagers.

Also, a stir plate helps oxygenation of your starter as well as reduced lag time and highest cell counts per volume, so can get away with a smaller starter that way as well.

I didn’t used to oxygenate, and even with proper pitch rates, would see 2-3 day lag on startup minimum. After oxygenation, it drops lag to somewhere between 12-24 hours for lagers.

 

[LitBrewing]

Small update, gravity is down to 1.050 after about 68 hours in the fermenter. Something is stirring in there but it's not super strong yet. I went ahead and just bought 3 more WYL800 packs and pitched them. I was worried about having 2 more days of low activity being bad for the beer while I grow the starter.
Next time I will make a starter!! Lesson learned pay attention to the amount of cells you need.