To pitch or not to pitch?

[andrewb_1985]

Hi all,
Yesterday I made a 4L yeast starter with 2 smack packs of 3068 for my Hefe I brewed today. I have had absolutely no activity in my starter. From what Ive read this yeast is very active.

The packs swelled up big and my starter and yeast were both at room temp before pitching which was about 72F. Starter gravity was 1.038. I immediately moved the starter to my basement where it's about 65F. I always use oxygen before pitching and a stir plate and I'm pretty obsessive about my sanitation. Normally I have a good Krausen going by now with other yeast strains I've used.

Just wondering how I can check if it's infected or not. Would there be a smell or any other signs? Was it too warm when i pitched the yeast? Ijust don't feel confident pitching this into my wort.

 

[SeattleMatt]

Sounds like you did everything right. You could cold crash it over night in the fridge, decant the beer, and check the gravity to see if it fermented. You can’t easily check for contamination without plating... there are some tests but nothing quick.

 

[IslandLizard]

Starters propagate best at prevailing room temps, 70-76F, no need for much temp control there, we don't care about the quality of the starter beer, it's oxidized anyway. Now even at 65F they still should grow, especially that Hefe yeast.

When making starters on stir plates, we actually don't see much krausen and foam, as the yeast keeps propagating, which is what we want. A little foam forming at some point is OK, but if it doesn't, so be it. The starter beer also gets much lighter as more yeast is being formed. After a good cold crash you should see a large amount of yeast settled on the bottom of the starter vessel. Then you know it worked.

You cannot tell if anything got infected until it shows signs, visually or by taste/aroma. If there's no reason to expect infections, don't start looking for them.

Definitely oxygenate the wort and pitch that starter. How large is that batch?

 

[andrewb_1985]

Thanks for the replies. How long should I wait before cold crashing? And do you think I should bring it back upstairs at 72F? It's a 14gal batch

 

[IslandLizard]

How long has it been on the stir plate? You should see that color change after 1-2 days if the yeast is good and vital, as it should be in your case with 2 fresh packs that swelled up.
For old yeast that has been stored in the fridge for 6 months, or longer, it could take a week on a stir plate to see that color change, then give it a few more days after that.

I would bring it upstairs, ASAP.

If you're planning to brew this weekend you're running out of time for cold crashing, it takes a few (3-5) days with that yeast, it's a very slow flocculator. You could let it run 1 or 2 more days on the plate, then pitch the whole starter, without cold crashing. The yeast is much more vital when pitched without cold crashing. You really can't detect there is 4 liters of starter beer in 14 gallons, many have tried to find that evidence.

 

[flars]

Do you use a refractometer or hydrometer for SG? I would check the SG of the starter since you already have the wort ready for pitching. If using a hydrometer the shipping tube will require less volume than the special sample cylinders.

This is just a quick thought and may be totally insane. I might consider starting some fermentation activity with US-05 if you are worried about keeping the wort free of infection if the 3068 starter has not fermented out.

 

[IslandLizard]

Do you use a refractometer or hydrometer for SG? I would check the SG of the starter since you already have the wort ready for pitching. If using a hydrometer the shipping tube will require less volume than the special sample cylinders.

Of course! Take a gravity reading!

Beware of the hydrometer shipping tubes, some have a stopper in the bottom that will drop out. Tape it down really well before using it for samples.

It's unclear if the OP has brewed his main batch already. If he did, yeah, waiting 2-3 days before pitching is out, and US-05 can save the batch.

 

[andrewb_1985]

I use a hydrometer for SG readings. What SG would I be looking for in my starter?
It's coming up on 48 hours on the stir plate. 24 hours at 65F then 24 hours at 72 to 76F.
I have already brewed and my wort it currently in a fridge at pitching temp. I've left wort sitting around for a few days before and it hasn't seemed to hurt it. So if my starter needs more time I think it's better the yeast is at full strenght

 

[flars]

I use a hydrometer for SG readings. What SG would I be looking for in my starter?
It's coming up on 48 hours on the stir plate. 24 hours at 65F then 24 hours at 72 to 76F.
I have already brewed and my wort it currently in a fridge at pitching temp. I've left wort sitting around for a few days before and it hasn't seemed to hurt it. So if my starter needs more time I think it's better the yeast is at full strenght

With WY 3068 I would expect an SG of 1.010 to 1.008 for the finished starter wort.

 

[IslandLizard]

If you trust your sanitation practices, you can pitch the content of the hydrometer tube after the reading, along with the rest of the starter.

 

[andrewb_1985]

With WY 3068 I would expect an SG of 1.010 to 1.008 for the finished starter wort.

So I ended up just cold crashing my starter after 52 hours. I left it for 24 hours in the fridge and just took it out and measured the FG of the beer at 1.023, compensating for temperature of course. So why are my numbers so far off from your estimate and what can I do about it? I have a spare 3068 in my fridge I purchased but didnt use.

 

[flars]

I would pitch a pack pf US-05 to get some fermentation going given the amount of time your wort has been at fermentation temperature.

Bring your 4 liter starter out of the frig and warm it to room temperature by swirling or in a water bath by gradually raising the temperature of the water bath to room temperature. Warming too quickly will shock the yeast. Once the starter is at room temperature swirl it frequently to see if a krausen starts forming. Do you recall the packaging dates of the two packs you pitched? Very old yeast with low viability can take an extended time to ferment out a starter wort.

When you warm the 4 liter starter and see some krausen forming after aerating by swirling the pitched yeast may have been of very low vitality. It is possible for low vitality yeast to take more than several days to ferment a starter wort completely.

What is the date on your spare pack of WY 3068? I would use this one now to begin a small starter to pitch. Use one of these calculators just to get an estimate of the number of new cells that will be propagated.
http://www.brewunited.com/yeast_calculator.php
https://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/
You will still get the ester formation of 3068 pitching it later even though the 05 has started the fermentation.

 

[andrewb_1985]

What is the date on your spare pack of WY 3068? I would use this one now to begin a small starter to pitch. Use one of these calculators just to get an estimate of the number of new cells that will be propagated.

All 3 packs were dated Jun 6th, 2018

 

[IslandLizard]

measured the FG of the beer at 1.023

Refractometer or hydrometer?

 

[IslandLizard]

Did you pitch that crashed slurry? I hope so.

How much slurry (estimated volume and consistency) did it yield after crashing? A half inch yeast layer on the bottom of a 5 liter flask is a lot of yeast.

 

[andrewb_1985]

Did you pitch that crashed slurry? I hope so.

How much slurry (estimated volume and consistency) did it yield after crashing? A half inch yeast layer on the bottom of a 5 liter flask is a lot of yeast.

Yes I pitched it. I also added my 3rd pack just to be safe. No starter for it just let it swell for 8 hours and pitched. I would say I had maybe 0.5l of good slurry. Not as much as I've had in the past tho.

Refractometer or hydrometer?

Hydrometer

 

[IslandLizard]

Depending on how thick that slurry was, 500 ml in a 15 gallon batch would be considered anywhere between a decent to overly large pitch.
A vitality starter or a "shaken-not-stirred" would have been much better than just a swollen pack, just my observation. But chances are, you probably didn't even need it.

So how long was that wort kept and at what temperature?

At 1.023 FG from 1.038 OG, something weird was definitely going on with that yeast or starter. Even at 65F.

 

[andrewb_1985]

So how long was that wort kept and at what temperature?

It was at 65F for 24 hours. After your recommendation to bring it back upstairs I brought it up. The temperature upstairs ranged from 76 during the day to 72 overnight. Total time until I cold crashed it was 52 hours. In the past I've made my starters Friday morning, brewed saturday, cold crashed sat night, and Sunday morning decant raise to pitch temp and pitch. Has worked fine for me every time. Maybe should be noted this is only my second batch using a stir plate. One would think that would only make things better.

A vitality starter or a "shaken-not-stirred" would have been much better than just a swollen pack, just my observation

Not exactly sure what you mean by vitality starter. I know pitching a straight swollen pack isn't the best but most other brewers I know only do that.