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General Category => Yeast and Fermentation => Topic started by: metron-brewer on April 29, 2015, 08:29:36 am

Title: 2 or 3 Packs Dry Yeast for Lager
Post by: metron-brewer on April 29, 2015, 08:29:36 am
I'm planning on a 1.048 German Pils using W-34/70 for the first time. Yeast packs dated 01-2016 so production date 01-2014 and 69% viable. BeerSmith says I need 353 billion cells and (2) packs of yeast yielding 276 billion, a bit of an under pitch as calculated by BeerSmith. Mr. Malty indicates using 2.50 packs yielding approximately 345 billion cells. The cost of the third pack is not an issue, just want to make the best beer.
So my question is, pitch 2 packs at 276 billion, or 3 packs at 414 billion?

I have not decided on the mach schedule yet, may just do a single infusion but the Recipe Specifics:
Recipe: German Pils
Brewer: Ron
Asst Brewer:
Style: German Pilsner (Pils)
TYPE: All Grain
Taste: (30.0)

Recipe Specifications
--------------------------
Boil Size: 7.98 gal
Post Boil Volume: 5.98 gal
Batch Size (fermenter): 5.25 gal   
Bottling Volume: 5.25 gal
Estimated OG: 1.0479 SG
Estimated Color: 3.0 SRM
Estimated IBU: 38.3 IBUs
Brewhouse Efficiency: 75.00 %
Est Mash Efficiency: 82.1 %
Boil Time: 60 Minutes

Ingredients:
------------
Amt                   Name                                     Type          #        %/IBU         
9.00 lb               Best Malz Pilsen Malt (2 Row) German Pil Grain         1        100.0 %       
2.00 oz               Hallertauer [3.10 %] - Boil 60.0 min     Hop           2        23.5 IBUs     
1.00 oz               Hallertauer [3.10 %] - Boil 30.0 min     Hop           3        9.0 IBUs     
1.00 oz               Hallertauer [3.10 %] - Boil 15.0 min     Hop           4        5.8 IBUs     
1.00 Items            Immersion Chiller/Pump (Boil 15.0 mins)  Other         5        -             
0.50 tsp              Yeast Nutrient (Boil 10.0 mins)          Other         6        -             
0.50 Items            Whirlfloc Tablet (Boil 5.0 mins)         Fining        7        -             
1.00 oz               Huell Melon [4.50 %] - Boil 0.0 min      Hop           8        0.0 IBUs     
2.0 pkg               Saflager Lager (DCL/Fermentis #W-34/70)  Yeast         9        -             


Mash Schedule: Single Infusion, Medium Body, Batch Sparge
Total Grain Weight: 9.00 lb
----------------------------
Name              Description                             Step Temperat Step Time     
Mash In           Add 14.00 qt of water at 154.9 F        145.0 F       45 min       
Mash Out          Add 8.00 qt of water at 189.3 F         160.0 F       45 min       

Sparge: Batch sparge with 2 steps (Drain mash tun , 3.56gal) of 185.0 F water
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: morticaixavier on April 29, 2015, 08:35:57 am
you're probably fine with the two packs.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: HoosierBrew on April 29, 2015, 08:40:21 am
you're probably fine with the two packs.

+1.  Plenty for a 1.048 beer IMO.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: metron-brewer on April 29, 2015, 08:41:39 am
(2) It is. Thanks Guys!
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: metron-brewer on April 29, 2015, 08:50:58 am
Maybe just a follow up here. Why would it be ok to under pitch with dry yeast but not with liquid?
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: HoosierBrew on April 29, 2015, 08:59:43 am
I don't think it's ever a good idea to underpitch a lager (or any beer) in a significant way. But for a sub 1.050 lager, I've had good results (clean beer, good attenuation) rehydrating two packs. And I've seen several brewers here and elsewhere who reported good results doing the same. Worst case you could always hit it exactly and pitch the extra half pack.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: jtoots on April 29, 2015, 09:00:39 am
Worst case you could always hit it exactly and pitch the extra half pack.

That's what I was thinking, but lots of experience above saving you a few bucks.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: morticaixavier on April 29, 2015, 09:00:48 am
Maybe just a follow up here. Why would it be ok to under pitch with dry yeast but not with liquid?

three reasons,

first, at the levels of underpitch you are talking about there is just not that much to worry about even with liquid.

second, the calculators tend to be very conservative about yeast viability over time anyway.

Third, these are all just estimates and you are likley within the margin of error anway.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: metron-brewer on April 29, 2015, 09:06:35 am
Thanks guys, appreciate it.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: S. cerevisiae on April 29, 2015, 09:59:10 am
Yeast cultures are kind of like nuclear weapons in that being close to the target is more than adequate to get the the job done.  The difference between 276 billion cells and 353 billion cells is not even a full replication cycle.  The yeast biomass cell count grows roughly at a rate of 2n, where n is the number of minutes that have elapsed since the end of the lag phase divided by 90 at 25C.  The replication period lengthens as fermentation temperature decreases.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: rabeb25 on April 30, 2015, 06:24:47 am
Your Pitch Rate for this particular venture is dependent on your fermentation temp... what is that going to be?
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: metron-brewer on April 30, 2015, 06:32:41 am
Your Pitch Rate for this particular venture is dependent on your fermentation temp... what is that going to be?

The yeast is rated 48-59, I'm planning on running to the lower end, 48-50 degrees.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: rabeb25 on April 30, 2015, 06:55:01 am
Then I strongly suggest you look at the manufacturers pitch rate for that temp.. because it GREATLY differs at that low range.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: beersk on April 30, 2015, 07:01:48 am
Yeast cultures are kind of like nuclear weapons in that being close to the target is more than adequate to get the the job done.  The difference between 276 billion cells and 353 billion cells is not even a full replication cycle.  The yeast biomass cell count grows roughly at a rate of 2n, where n is the number of minutes that have elapsed since the end of the lag phase divided by 90 at 25C.  The replication period lengthens as fermentation temperature decreases.
This is good to know. Thanks.

I've always pitched 2 packs of 34/70 (rehydrated) and it worked out just fine.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: metron-brewer on April 30, 2015, 07:12:32 am
Then I strongly suggest you look at the manufacturers pitch rate for that temp.. because it GREATLY differs at that low range.

Per the spec sheet:
"increase dosage for pitching below 12°C (53°F), up to 200 to 300 g/hl at 9°C (48°F)"

So if I'm doing the math correctly, for 5.25 gallons, say 20 liters, fermenting at 48-50 degrees, I should be pitching somewhere between 40 to 60 grams of yeast. Basically 3 to 5 11.5 gram packets. Understanding that pitching "exactly per spec" may not be required in real world home brewing applications. And while two packets may work just fine and people have had great success with that, pitching 3 or 4 packets to me may be cheap insurance.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: rabeb25 on April 30, 2015, 08:27:26 am
The way I look at it is this...

Increase the pitch rate or the temp(personally I would do temp). 2 packs would be fine at 53ish(but not below). FWIW, YMMV, and all the other disclaimers.

You have to try pretty hard to over pitch a lager and I can guarantee you, you will never over pitch on the yeasts first fermentation. If your lager yeasts are not chewing though ~12 gravity points per day, you did not pitch enough yeast. For this beer in question, I would be at FG (1.010ish) 4 days from brewday.

Cheers, and good luck!
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: ynotbrusum on May 01, 2015, 02:29:08 pm
The way I look at it is this...

Increase the pitch rate or the temp(personally I would do temp). 2 packs would be fine at 53ish(but not below). FWIW, YMMV, and all the other disclaimers.

You have to try pretty hard to over pitch a lager and I can guarantee you, you will never over pitch on the yeasts first fermentation. If your lager yeasts are not chewing though ~12 gravity points per day, you did not pitch enough yeast. For this beer in question, I would be at FG (1.010ish) 4 days from brewday.

Cheers, and good luck!

But don't make the mistake of racking it just because it hit terminal gravity in those 4 or 5 days!  Let the yeast do some cleanup on a lager.  See the Brulosopher lager schedule for the short turn lager technique. You can go grain to glass in 24 days. It really works.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: S. cerevisiae on May 01, 2015, 06:01:12 pm
You guys are missing the big picture.  It does not make a darn bit of difference if one pitches 200 billion cells or 400 billions cells in a non-high gravity (i.e., non-hypertonic) solution, especially one that is fermented below the temperature at which most microflora give up the ghost. The maximum cell density for 1 liter is roughly 200 billion cells. A volume of 5.25 US gallons is approximately equal to 20 liters; therefore, the maximum cell density for 20 liters is 20 x 200 billion = 4 trillion cells.  Unless one pitches 4 trillion cells, the fermentation is going to experience a period of exponential growth.  What matters is dissolved O2 and the amount of carbon that is available to the yeast cells. Sugar is carbon bound to water; hence, the term carbohydrate (all of the sugars found in wort are multiples of CH2O). Yeast cells consume carbon.  Given enough carbon and O2, one could fully attenuate a batch of wort by pitching just one yeast cell.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: metron-brewer on May 01, 2015, 06:11:45 pm
I am planning on pitching two packs of yeast. I am also planning on bumping my fermentation temp up to 53.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: bengelbrau on May 01, 2015, 07:43:02 pm
Relax... I had a 1.095 OG doppelbock, pitched with one pack of 34-70 (non-rehydrated), and scored a 42 in the first round of NHC. The wort was well O2ed, and the pitch rate was sufficient to yield a great beer.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: metron-brewer on May 01, 2015, 07:55:28 pm
Relaxed for sure. Thanks for all the input.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: majorvices on May 03, 2015, 04:50:20 am
I am planning on pitching two packs of yeast. I am also planning on bumping my fermentation temp up to 53.

I'd keep the temp a little lower for a pils and that strain. 48-50 with 2 rehydrated packs will be fine. I'm brewing a pils next week with the same strain - 12 gallons and 4 packs @ 48 degrees.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: rabeb25 on May 04, 2015, 06:45:11 am
The way I look at it is this...

Increase the pitch rate or the temp(personally I would do temp). 2 packs would be fine at 53ish(but not below). FWIW, YMMV, and all the other disclaimers.

You have to try pretty hard to over pitch a lager and I can guarantee you, you will never over pitch on the yeasts first fermentation. If your lager yeasts are not chewing though ~12 gravity points per day, you did not pitch enough yeast. For this beer in question, I would be at FG (1.010ish) 4 days from brewday.

Cheers, and good luck!

But don't make the mistake of racking it just because it hit terminal gravity in those 4 or 5 days!  Let the yeast do some cleanup on a lager.  See the Brulosopher lager schedule for the short turn lager technique. You can go grain to glass in 24 days. It really works.

No offense to Brulospher(I read all his stuff, and he will tell you this as well), but he did not come up with this lager method. It is based off the Narziss Method, which has been around for quite some time (50+ years???). I have been doing my accelerated lager method (also based off Narziss, and slightly different from Brulospher for close to 12 years). I have no issues going grain to glass in 14 days (sometimes less) However.. My accelerating method is not to push beer to serving as fast as possible, its to free up fermenters. I have attached my latest lager.. OG 1.050, FG 1.009. FG hit in ~5 days from brew day. Ferment temp 53f. Beer is now going to 30f where it will sits for ~3-5 days and then be kegged.

(https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-xpf1/t31.0-8/11159879_572512616224676_805775188621344028_o.jpg)
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: rabeb25 on May 04, 2015, 06:51:59 am
You guys are missing the big picture.  It does not make a darn bit of difference if one pitches 200 billion cells or 400 billions cells in a non-high gravity (i.e., non-hypertonic) solution, especially one that is fermented below the temperature at which most microflora give up the ghost. The maximum cell density for 1 liter is roughly 200 billion cells. A volume of 5.25 US gallons is approximately equal to 20 liters; therefore, the maximum cell density for 20 liters is 20 x 200 billion = 4 trillion cells.  Unless one pitches 4 trillion cells, the fermentation is going to experience a period of exponential growth.  What matters is dissolved O2 and the amount of carbon that is available to the yeast cells. Sugar is carbon bound to water; hence, the term carbohydrate (all of the sugars found in wort are multiples of CH2O). Yeast cells consume carbon.  Given enough carbon and O2, one could fully attenuate a batch of wort by pitching just one yeast cell.

Sure, you CAN...You CAN do a lot of things.. It all matters what your end game is. Do you want to pitch one cell and wait a year for your FG to be hit? Cool! However, I don't, so I pitch proper amounts of healthy yeast, with plenty of pure O2, at the proper pH and "proper" fermentation times.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: hopfenundmalz on May 04, 2015, 07:01:54 am
The way I look at it is this...

Increase the pitch rate or the temp(personally I would do temp). 2 packs would be fine at 53ish(but not below). FWIW, YMMV, and all the other disclaimers.

You have to try pretty hard to over pitch a lager and I can guarantee you, you will never over pitch on the yeasts first fermentation. If your lager yeasts are not chewing though ~12 gravity points per day, you did not pitch enough yeast. For this beer in question, I would be at FG (1.010ish) 4 days from brewday.

Cheers, and good luck!

But don't make the mistake of racking it just because it hit terminal gravity in those 4 or 5 days!  Let the yeast do some cleanup on a lager.  See the Brulosopher lager schedule for the short turn lager technique. You can go grain to glass in 24 days. It really works.

No offense to Brulospher(I read all his stuff, and he will tell you this as well), but he did not come up with this lager method. It is based off the Narziss Method, which has been around for quite some time (50+ years???). I have been doing my accelerated lager method (also based off Narziss, and slightly different from Brulospher for close to 12 years). I have no issues going grain to glass in 14 days (sometimes less) However.. My accelerating method is not to push beer to serving as fast as possible, its to free up fermenters. I have attached my latest lager.. OG 1.050, FG 1.009. FG hit in ~5 days from brew day. Ferment temp 53f. Beer is now going to 30f where it will sits for ~3-5 days and then be kegged.

(https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-xpf1/t31.0-8/11159879_572512616224676_805775188621344028_o.jpg)

I have said the same on here, have been doing it for 4 or 5 years, like the results. It does free up the conical quickly during lager season.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: metron-brewer on May 04, 2015, 07:17:51 am
Alright to circle back and summarize.
Per Mark (S. cerevisiae) Pitching in to a low gravity wort is almost like pitching into a starter, pitch into well oxygenated wort and a slight under pitch will not affect the outcome of the fermentation.

Per Keith (majorvices), this yeast is plenty capable of fermentation at temperatures of 48-50 degrees even though the manufacturers spec sheet indicates an "ideal" temp of 53 to 59.

Since I am not concerned with a quick turnaround, and in the spirit of home brewing, "try it yourself to see what works", I will be pitching (2) packets of re-hydrated yeast into well oxygenated wort in the neighborhood of 1.048, and fermenting in the 48-50 degree range.

Cheers Guys and again, thanks for all the input.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: metron-brewer on July 16, 2015, 11:02:58 am
I just wanted to post the results of this brew.
Brewed 05-31-2015 O.G. 1.044, pitched (2) packs re-hydrated 34/70 at a temp of 49, Set Point temp of 48 = fermentation temps of 48-50. After no activity the first day I bumped the Set Point to 49. After the second day with no visible signs of fermentation I opened up the fermentor and took a gravity sample, there was no change from O.G., I bumped the Set Point another degree to 50 so fermentation temp should run 50-52. On the third day following brewing I again opened up the fermentor and found a full head of kreausen. On 06-24-2015,  I took a final gravity reading of 1.012, calculated 72%AA, yeast is rated 73-77. I detected no off flavors. I let the beer sit on the yeast for another 12 days for clean up and kegged on 07-06-2015. Took a taste test last night and it's very tasty. I detected a pretty subtle faint sweetness to it. I'm going to enter it in the 2015 Minnesota State Fair competition so we'll see what the judges think of my first ever Pils.

As a side or follow up, I harvested the yeast on 07-06 and re-pitched the slurry into a "Hoppy Pils" on 07-12-2015. Fermentation at 50-52 degrees and it took off in less than a day developing a full head of kreausen within 24 hours.
Title: Re: 2 or 3 Packs Dry Yeast for Lager
Post by: ynotbrusum on July 16, 2015, 12:12:51 pm
Congrats!  I hope your beer does well in the competition.

I never responded to the points above about Brulosopher, but I readily acknowledge the Narziss source and did not mean to imply that Marshall came up with it...but he has recently advocated for it.

And, truth be told, there are lager Brewers winning awards with the old school way of pitching warm and slowly dropping to fermentation temp upon visible signs of fermentation appearing.  So YMMV for sure.

What has me convinced in terms of a relatively newer thought  (to my understanding, at least) is Mark's view about pitching highest vitality yeast, rather than quiescent yeast.  That is probably another old school thought, too, but I had not heard about it before.

To the OP - be very sanitary when repitching yeasts.  Many suggest avoiding it entirely in the warmer months due to the level of airborne contaminants...but again YMMV.