Did my warm lager yeast starter cause my fermentation to lag

Beerandgranite

I have been overbuilding starters to propagate for the next batch, and have been successful with two batches starting from a single pack of L13. In both cases fermentation began within 12 hours. However this third batch has gone 48 hours with zero airlock activity. At first I assumed I had a leak, however the gravity has not changed. The only thing I could think of is a ran the starter that I pitched on this batch at ambient temp (72-75 degrees) as opposed to 65 degrees. Could this have cause the yeast to not tolerate the cold pitch and fermentation temperature (50 degrees)?

Beer666

Should not be a problem as its common practice. How big a starter, whats your wort OG/ grist? What are you fermenting at?

McMullan

It's recommended to culture lager yeast at propagation temperatures, not recommended fermentation temperatures. Your ambient temperature wasn't the problem. It's possible the yeast cells were shocked at pitching by temperature differences between starter culture and FV wort. This redirects yeast metabolism away from processing sugars and delays things up to a day or so. To make things potentially worse, a starter not pitched fresh has lower cell viability and lower vitality. The result is usually an artificially long delay in fermentation starting.

Beer666

I stopped making lager starters a long time ago. I pitch 3 packs of dried yeast (27l of 1040 wort) and reuse the slurry next time. I do this about five times and then use fresh yeast;

Beerandgranite

Starter was 1.8 liters and roughly 400b cells. Wort og was 1051, 90%pilsner 8% vienna 2% melanoidin/carapils. just checked it again this morning (54 hours) and still no action on the airlock, although i wasn't able to check the gravity. pitched at 50 degrees f and fermenting at 50 degrees f. think i should warm it up and see if anything happens? I also have an additional 200b cells i set aside that i could pitch.

Beerandgranite

So that would be the temperature the starter was stored at vs the temperature of the wort it was pitched into? i had the starter stored in a 40 degree chamber and pulled it out to ambient temp about 30 mins before pitching it into 50 degree wort. perhaps i didnt give it enough time to warm up? I would consider the start relatively fresh, went like this:
Day 1: pulled out 200b cells from previously overbuilt starter, added to 1.6L starter.Day 3: after 48 hours @ 72-75 degrees poured off .9 liters of slurry, cold crashed remaining .7 Liters Day 4: Decanted starter, and added 1.6Liters of new starter Day 6: after 72hours @72-75 degrees, set aside starter to be cold crashed Day 8: Pitch I just checked my fermentor again this morning (56 Hours from pitch) and still no action. any recommendations on how to proceed? I have 200b more cells I could pitch, however its from the same starter. i also have the ability to raise the temperature.

Beerandgranite

I like this approach. I am planning on brewing again this weekend, and instead of using the overbuilt starter that I have leftover, im considering pitching my wort onto the yeast of a pilsner i am going to keg the day before.

McMullan

How do you know there were about 200b cells to start with and when was the previously prepped starter made? How much wort's in the FV? How did you aerate the wort? Starter size is small, assuming a standard 5 gallon batch. Decanting any so soon probably dumped good yeast. With small starter volumes just doubled you might have just fed the yeast rather than cultured them. I'd step up about 5x, e.g., 500ml to 2500ml. Aerate the starter wort well. If the gravity of your current brew doesn't start dropping by day 4 I'd pitch some dry yeast.

Deadalus

I had an unusual start to a lager I brewed on Sunday where it was also slow. It was a different liquid yeast. It was built from an overbuilt starter I had banked (about 250 ml) and stepped back up to 1.8l. I had let it build for 2-3 days then cold crashed. I decanted it and let it warm up some before pitching. It was late night when I pitched it. It formed this lighter layer at the top and didn't mix. I thought it would drop but it didn't. Not much activity showing the next morning but it dropped four points per the Tilt. The band just moved down slightly. Next day, Tilt shows no change but the band had moved further down. I'm a bit unsure as I can't remember seeing banding before. I thought it was perhaps a specific gravity difference between the wort and starter. It being lager yeast I expected them to sink to the bottom. I just got a new IR thermometer, so I checked the temps bottom to top. Bottom was 51, middle aboutv53 but past the band at top was 58! The yeast were just working in the top band. Almost no activity mind you showing. So I shook the carboy. It was like shaking a soda bottle. Instant foam at the top from CO2! Then I gave the carboy a nice rocking circular shaking. It's been fine since, not particularly far apart on temperatures top to bottom.
Short answer, maybe shake it some and set the temp a little higher. Myself I usually stir it with the wine thief when taking initial gravity but I didn't here because it was a too hot to pitch when I took it.

Beerandgranite

all calculations are rough using an online calculator. im basically working it out using the volume. if after inputting starer og, volume, starting cell count the calculator says my 1.6 liter contains X cells, i take X/16 to get cells per 100ml of slurry. on the previous started i set aside 900ml of slurry @ 22b cells per 100ml = 198b cells (i am aware this could be off by some percentage). i then used that 900 ml (cold crashed and decanted) as the the original cell count for the starter i used for this brew. the previous starter and brew that this 900ml came from was only a week and a half before. Aeration admittedly is not great, i am just letting the wort (6 5.75 gallons) splash out of the valve on the kettle into the fermentor, about a two foot drop. i feel there is definitely alot to be improved upon here

Beerandgranite

When you step up that many times do you cold crash and decant each time before adding the next volume of starter wort? and if so, how long does it typically take you to get to 2500ml?

McMullan

I meant 5x in terms of volume, but, no, I wouldn't decant off the spent wort between step ups. There's still a lot of cell budding going on up to 3 days or so, even when it looks quiet. No point dumping good cells.

Beerandgranite

Praise Yahweh it started fermenting ans I’m at 1.035. It appears there is a leak somewhere in my fermenter, however I do still think there are some yeast issues given that it’s only dropped 15 points 5 days in

Beerandgranite

What’s even more astounding is that after 15 minutes my sample started bubbling like crazy and after an hour has dropped down to 1.025. I have taken this as a que and upped my fermentation temp in hopes of getting this fermentation going

Beer666

If i have fresh wort the day i keg i pour all the yeast cake into a clean fermenter. Saves having to clean and sterilise a bottle and store it in the fridge.

Beerandgranite

Kegged the pilsner, jarred the yeast, confirmed the pilsner came out as intended, pitched the jar of yeast a few hours later into a maibock. the maibock is now humming away only 8 hours after pitching. for sure going to be my go to method for lagers from here on out.