Lager Attenuation

I don't have any experience or data on S-189, but that grain bill is not particularly fermentable. So maybe you are at/close to what you can expect.

 

I'd say it's done, looking at the grain bill. What Munich did you use? Light or Dark?

In cases like this where there is no easily fermentable sugars (pils malt), attenuation will go down unless you step mash and such.

 

I just used S-189 for the first time recently. It was completely stuck at about 1.020 for 3 weeks. No amount of swirling or warming it up did anything to move it. Then I added dry hops. Suddenly it woke up again and finished at 1.013 (from 1.062).

So I do think it's a fussy yeast. Add dry hops, or yeast energizer, and hope for the best.

 

Probably underpitched @ 1 sachet

 

Definitely fine then.

 

I would point at the grain bill. I use S-189 a lot and never have had problems. I brew different lagers all the time from around 1.050 - 1.065 OG. I pitch a single pack without re-hydration. They all finish out. Next time use some Pils malt That will help out. Take care!

 

I'll nitpick here...while agree that Pils would provide a more fermentable wort when done side by side with the same mash protocol as most Munich malts, not sure if "easily fermentable sugars" is the right term here. Munich should provide more non-fermentable Maillard products, but still should provide a fairly similar proportion of easily fermentables like glucose and maltose. A German Munich like Weyermann's Munich I should be almost as fermentable as their Pils...couple points maybe but it's not like the wort would be loaded with maltotriose when compared.

 

FWIW, Greg Doss' study (circa 2012) found Munich Malt to be slightly less fermentable than Pils. But there's more to @Yalc's grain bill than the Munich. It also contained healthy portions of Aromatic and Blackprinz, which would be even less and lesser fermentable, respectively.

 

I like s-189 and I think this is finished based on your grain bill and nothing to do with your yeast.

 

Even at 2.5 gal batch, one pack is under pitched. By my calculations, you need closer to two packs, 200B cells vs. one pack 110B cells. I'm not disagreeing with the general consensus regarding grain bill being the main factor of higher than anticipated FG. Rather bringing pitch rate up for future consideration - lagers take a shit ton of yeast!

 

2.5ml/mil for me. However, since most homebrewers treat lagers like ales (ferment warmer, raise temps, etc) they can use pitch rates much less. But, this is exactly why 99% of homebrewed lagers taste like ales, so...

 

Do you have a reference for a sachet of S-189 containing 110 billion cells?

Cheers!

 

I've heard from random sources on the interwebs that I deem credible that a typical dry yeast pack contains 100-200 billion cells. Very lengthy discussion topic, filter the chaff yourself (and yes it's largely chaff):

https://www.homebrewersassociation.org/forum/index.php?topic=27438.0

 

According to Brad Smith:

“Dry yeast has approximately 18 billion cells per gram of yeast. Dry yeast packets typically come in two sizes. The 5 gram (smaller) packets have approximately 90 billion cells, which is comparable to a recently purchased liquid yeast vial or large smack pack (each at 100 billion cells). The larger 11.5 gram dry yeast packets have approximately 207 billion cells,…”

http://beersmith.com/blog/2014/04/03/dry-yeast-in-home-brewed-beer/

Cheers!

 

Little late getting back to this one...but nobody actually quoted the sources. Fermentis states at least 6 billion viable cells per gram or at least 70 billion per sachet. Lallemand states at least 5 billion viable cells per gram or 55 billion per sachet.

Do we have credible sources that have done cell counts on approximate viable cells in sachets that are double to quadruple the stated counts from the manufacturers? I know I've been dinged in my papers for stating 100-200 billion estimates . . .

 

Found a reference. I'll look for more.

I apparently heard Jamil say on the following podcast at about the 59-minute mark that the standard 11-gram dry yeast packets contain about 225% as much yeast as a standard vial of liquid yeast. I mean, he would know, right? He wrote the book on Yeast.

http://www.thebrewingnetwork.com/membersarchive/bws_2016_07_05_diacetyldryyeastQs.mp3

https://www.homebrewersassociation.org/forum/index.php?topic=27438.msg358328#msg358328

Note: Jamil didn't state his assumptions, so we can only assume what he assumed. In context I think it was pretty clear what he was saying -- there's generally a lot more viable yeast in a dry pack that what meets the eye. Not to mention, dry packs remain mostly viable for YEARS in the fridge instead of just 8-10 months like liquid yeast does.