WLP090 starter behaving strange

[The M]

I've made dozens of starters but this one's first when I'm not sure if everything is OK. Cooked up the 2L starter last night and pitched WLP090. As I pitched the yeast I noticed that the best by date was actually 2nd of April. Didn't worry too much because White Labs yeasts have been so reliable. Anyway I woke up this morning and at some point went to see how the starter was doing. To my surprise I found that the krausen was absent. I looked closer and couldn't see any activity after 12 hours of pitching the yeast. Switched off the stir plate for an hour and I thought that I'll dump the starter. Then I realized the yeast was quite old and turned the stir plate on again. I decided to let it spin for couple of hours more and then the miracle happened. There was some activity after an hour and now after about 9 hours later still no krausen. There's only light foam on top of the starter (see the pic) and bubbles are running from bottom. So activity is there but just barely. I have brewed with WLP090 several times but I can't recall seeing any of my previous starters (with any yeast) acting like this. I usually get quite big krausens with every starters I whip up. I will step up this one as I just want to be sure that there's enough cells for my next batch. I'm just puzzled because this is the first starter which has behaved like this. Anyone else have similar experiences and any thoughts should I be worried?

 

[marc1]

You could let it go for a couple days and then crash it and check the gravity.

 

[VikeMan]

I've seen lots of stir plate starters without much foam/krausen. I wouldn't waste one minute of worry on this. The color shows that there's a lot of yeast in suspension.

 

[The M]

Thanks guys for your replies. marc1 Yeah I was planning already to check the gravity once the activity has stopped

VikeMan Thx, that is reassuring. This is first one for me without any krausen. I've been doing starters for three years now after I switched from dry yeast to liquid ones and haven't seen starters behaving like this before. Do you have any explanation what might cause this. Is it the old yeast? From what I remember from previous WLP090 starters, the krausen has been clearly visible and quite moderate compared for example to WLP066 or even WLP810 starter which foamed like crazy last week

 

[Konadog]

How cold is it where your making this at? I have noticed less krausen, or taking longer for it to start if it's cold in my kitchen. That and being old, might be a few things that add up to your issue. I do agree, it looks fine so run it!

 

[VikeMan]

VikeMan Thx, that is reassuring. This is first one for me without any krausen. I've been doing starters for three years now after I switched from dry yeast to liquid ones and haven't seen starters behaving like this before. Do you have any explanation what might cause this. Is it the old yeast? From what I remember from previous WLP090 starters, the krausen has been clearly visible and quite moderate compared for example to WLP066 or even WLP810 starter which foamed like crazy last week

I can't really say in all cases why some show more foam than others, but here are some possibilities:
- Stir plate speed...faster stirring, less foam
- Krausen comes and goes while nobody's looking (like overnight)
- Soap/Detergent residue in the flask

 

[Brooothru]

I've seen lots of stir plate starters without much foam/krausen. I wouldn't waste one minute of worry on this. The color shows that there's a lot of yeast in suspension.

^^^This.

I've been doing some maintenance on yeast samples lately, including banked harvested yeasts, frozen banked samples dating back to 2016, and two unopened White Labs (one Pure Pitch, one vial), one which was one year past its Best By date, the other more than 18 months out of date.

It took multiple steps to revive each, but all of them resulted in developing at least 200 ml clean dense cakes after cold crashing and decanting. Let it sit (or slow spin on the stir plate) for another day or two. Then crash for 48 hours. Decant the majority of the top liquid when it stratifies, then fill your flask with 1~1 1/2 L fresh 1.040 starter wort on top of the yeast ring. Spin it for 48 hours. You'll have plenty of cells for a high gravity pitch.

WLP-090 is possibly the same thing or closely related to Pacman and Joystick, but I haven't use any of them in quite a long time, though I did just pick up some 090 for a future brew. And remember, not all yeasts throw off a huge krausen, even the strong fermenters like 090. It's fast and strong, but may not necessarily produce a thick viscous krausen. It may have happened so fast overnight that you just missed it.

 

[The M]

Well, it seems that I panicked way too early. As you all wrote there was nothing to worry about. Activity slowed down today about 36 hours after pitching yeast. I poured the starter into two mason jars and there is indeed nice yeast layer already in bottom of the jars. I'll keep the jars in the fridge over the weekend and make another starter on Monday just to be sure.

Konadog The temp shouldn't be issue in my kitchen. There's a constant temp about 20C (68F) in the room. Anyway I appreciate your reply

VikeMan Very good points. Stir plate speed is quite low because I don't want to stress the yeast. There wasn't any soap residue in the flask only some StarSan residue. Knowing how fast WLP090 performs you might be right that the krausen was there during the night

Brooothru Yeah, you're right about reviving yeast. I have previously revived 12 month old Imperial Juice and it worked like a charm. I'm aware that different yeasts throws different size of krausen but this was still first one I didn't see proper krausen at all. It's strange since I've been using WLP090 quite a lot and remember that there have been moderate krausen in previous starters. Looked up my brewing notes where I also add info about starters but there was no info about lack of krausen with WLP090 starters. I think that I was bit worried because this was new phenomenon for me. I bet that the krausen might have been there during overnight but who knows. At least I learned a new lesson (again) with this great hobby

I want to thank all of you once again. This truly is the place where you can always get help and info when you are puzzled. Cheers guys