Mexican Lager yeast - weird starter (floccy?)

[DJ_L3ThAL]

I've had a 50mL vial of white labs Mexican lager yeast which was healthy as it could be back in Feb 2015. Been stored in the fridge since.

Put it into a 1.020 600mL starter at 22C on Monday night, appeared to have normal activity within 24-48 hours so stepped that up to a 1.037 1L (1.6L total volume) starter but after 24 hours it now looks like this which I've never seen a yeast look like before... the floccs settle very quickly and the wort looks clear even while the store plate is spinning (ie. the yeast doesn't look to be in solution like it regularly does. It smells ok, maybe slightly fruity but otherwise "clean" like normal starters I've done. Have put in fridge to settle out overnight now.

Is it a tipper?

 

[nosco]

1968 does that but maybe not that extreme

 

[fungrel]

What temperature and time has your starter been on the plate for?

 

[technobabble66]

22°C for 24hrs, by the look of it

 

[technobabble66]

Instead of stepping straight up to the 5L step, maybe try a 2L step with 1.040 to see how it behaves?
Maybe you've discovered/created a new strain - instant floccing lager!!

 

[DJ_L3ThAL]

It has been 22C. On stir plate for 48 hrs first step and 24 hrs second step.

I oxygenated the first step and just set flow rate as low as possible (maybe 0.5L/min or less for 1.5mins), which was the only other factor I added in above my normal process.

 

[Dan Pratt]

007 looks like this and i think Irish 04 from memory.

It looks right to me.

 

[TheWiggman]

I've used Mexican lager once and all I can remember from it is I wasn't a fan of the results (no good for an Aussie lager, too bland would you believe). 'Fruity' aroma suits this yeast. Lager yeasts tend to be rather fluffy.
Personally I wouldn't use a >2 year old lager yeast but that's me. If you're only pitching it in a 5l test batch for fun then see how you go, otherwise you still have at least another step left for a standard 19-23l batch (and going from 1.3l you should decant and make your next step over 5l).

 

[DJ_L3ThAL]

Thanks guys, I've settled it out and will make next step 5L (largest flask I have). It's actually a double batch so I might proceed with it as worst case I only lose one keg, or have a second rate keg with a good one following closely after. Call it in the name of brewing science! Will report back!

Ps. Wiggman I used this in one of the U-Flecku kegs in 2015 and it was my preferred for that dark Czech lager over Budvar yeast... only marginally but daaamn it was clean.

 

[TheWiggman]

It would be perfect for some beers as it definitely reminded me of Corona. It didn't work well with PoR and didn't exhibit any of the cattiness we all know and love in the likes of VB and New. Damn now I'm sad about 2042 again
If you're doing a double batch why not put the WLP940 in one and something like S-23 or 34/70 in the other for comparison? It's going to be a pretty chronic underpitch otherwise, and if I've learnt anything in brewing it's that underpitching a lager yields undesirable results. Or prove me wrong, whatever.

 

[homebrewnewb]

i have 34/70 to donate for this experiment if you ping me in time!

 

[Black n Tan]

IMO it is pretty unusual behaviour for a lager yeast. Never seen it before but I have never used that specific yeast before. Generally yeast flocculation is inversely related to attenuation i.e.. high attenuation yeast are poorer flocculaters. So for a crisp Mexican style lager I would expect the yeast to be a low-medium flocculater and your photo suggests it is highly flocculant. I suspect the long storage has selected for a highly flocculant mutant (the flocculation may have been protective during the long storage and therefore selective) and it will result in lower attenuation in the beer. So personally I would ditch it and not risk 'flocking' up my beer.

 

[captain crumpet]

IMO it is pretty unusual behaviour for a lager yeast. Never seen it before but I have never used that specific yeast before. Generally yeast flocculation is inversely related to attenuation i.e.. high attenuation yeast are poorer flocculaters. So for a crisp Mexican style lager I would expect the yeast to be a low-medium flocculater and your photo suggests it is highly flocculant. I suspect the long storage has selected for a highly flocculant mutant (the flocculation may have been protective during the long storage and therefore selective) and it will result in lower attenuation in the beer. So personally I would ditch it and not risk 'flocking' up my beer.

Could this be checked with the FG of the starter?

 

[Black n Tan]

Could this be checked with the FG of the starter?

Not sure to be honest. I suspect a starter will attenuate higher than a typical beer because it is stirred and typically has a lower SG.

 

[VP Brewing]

007 looks like this and i think Irish 04 from memory.

It looks right to me.

Got Wlp 007 going now. Had a wine like smell and looked like the peanut butter my dog likes. Weird yeast.

 

[Black n Tan]

Well that is interesting and suggest the yeast is behaving as normal. It is intriguing. Whitelabs gives this yeast a 70-78% attenuation range, whereas most other lager yeast strains have only have a 5-6% range in attenuation levels. May be it just depends on when it decides to floc, but boy it should give a clear beer.

 

[DJ_L3ThAL]

Decanted off settled slurry and it smelled and tasted normal to me. Gravity was 1.009.

I had a recollection of when I dosed the oxygen at the first step the froth overflowed the flask, maybe I physically excluded the less flocculant yeasties at that stage? Who knows...

In the name of beer science step 3 is on the plate at 22C. Will pitch the settled slurry into half the batch this week and report in a few weeks, might even be sooner. I hope I've created some monster lager yeast mutant that can live with me forever

 

[DJ_L3ThAL]

8 hours later! Typical lager yeast sulphur aroma in fridge... promising!

 

[DJ_L3ThAL]

Update: this is fermenting away happily at 10C, has been since 10/8 continuous bubbling out the blow off.

Took a gravity reading last night it's at 1.038 from 1.048. Aroma has a slight Pear note (not expected but hopefully just the yeast during ferment throwing this) and taste is sweet (expected as still at 1.038). Nothing majorly out of whack so will proceed with the sample as a fast ferment test, looking good!

 

[DJ_L3ThAL]

Update: this finished at 1.007 and tastes clean. I lagered it for a couple of weeks, however the slurry I've saved is still quite chunky and competes with the trub/hop matter by looks of things so will be difficult to rinse into useable and clean yeast. Thoughts?