Dark Lager

The difference between an ale and a lager is that a lager uses bottom fermenting yeast that perform well at colder temperatures than ale yeasts.  A lager yeast can ferment down in the high 40s to low 50s where an ale yeast can only really get down to the low 60s.  Fermenting at this lower temperature range allows the yeast to produce a cleaner flavor profile than is found in ale.  This clean yeast profile lends itself to use in light refreshing beers like a pilsner (which the American Light Lagers are a variety of).  The trade off with the clean profile is that any flaws in the beer are more noticeable due to the yeast not hiding anything as might be the case in an ale.

To brew a lager requires a number of extra steps.  Since you ferment at such a low temperature the yeast need more help getting started so an extra large yeast starter needs to be built.  The yeast have some trouble cleaning up after themselves at lager temperatures so you need to raise the temperature up to the 60s towards the end of fermentation to allow the yeast to take care of diacetyl which is a butter/butterscotch flavored yeast byproduct (some people can't taste it apparently - not sure if I'm one of those people because I have never noticed it in any of my beers).  Finally, lager is typically given a long secondary storage time at near freezing temperature which is apparently critical for getting a clean, clear, and crisp beer.  These steps serve to make a lager a more challenging beer to brew than most ales.

I have decided to see if I'm up to the challenge of brewing a decent lager.

In Arizona brewing a lager could have prevented me from brewing any ale as the room temperatures were just a little too warm for ale fermentation.  Here in Pennsylvania, with my basement being in the low 60s during the winter, I can use the fermentation chamber for the long lager fermentation and storage time and still brew more ales while I wait.

I found a recipe in Craft Beer & Brewing magazine from Ron Pattinson called "1926 Barclay Perkins Dark Lager" that seemed like as good a recipe to start lager brewing on as any - I really like a dunkel lager.

Recipe Details:

• Grain:
• 10 lbs 12 oz Pilsner
• 2 lbs 4 oz Crystal 60L
• 4 oz Roasted Barley
• Hops:
• 0.5 oz Saaz (Pellet, 3.0% AA) at 60 min
• 0.5 oz Saaz (Pellet, 3.0% AA) at 30 min
• 1.25 oz Saaz (Pellet, 3.0% AA) at 10 min
• 0.75 oz Saaz (Pellet, 3.0% AA) at 0 min
• Yeast:
• White Labs 838 Southern German Lager Yeast
• Water:
• 10 gal Spring Water
• 1 tsp Calcium Chloride
• 1 tsp Gypsum
• 1 tsp Irish Moss at 20 min

Process Details:

• Batch Size:
• 6 gal
• Mash:
• 157 F for 60 min (Target 154 F)
• Boil:
• 60 min
• Fermentation Temperature:
• Primary at 48 F
• Diacetyl Cleanup at 61 F
• Lager at 36 F
• Primary Duration:
• 2 Weeks
• Diacetyl Cleanup Duration:
• 1 Week
• Secondary/Lager Duration:
• 6 Weeks

Results:

• OG:
• 1.054 (Target 1.057)
• Efficiency:
• 67% (Target 71%)
• FG:
• 1.020 (Target 1.016)
• Apparent Attenuation:
• 62% (Target 71%)
• ABV:
• 4.46% (Target 5.38%)

Brewing Notes:

• 12/6/14 - I did some research and found that pitching a large amount of yeast at lager fermentation temperatures was probably the way to go.  My vial of yeast was 3 months old so I determined (using this tool) that I would need to build about 4 liters of yeast starter (assuming 1.5 million cells/ml/degree plato).  My flask is only 2 liters so I would have to do a two stage starter.  I added 7.5 oz of DME to 2 liters of tap water and boiled it in the flask.  Let it chill to the low 60s over night.
• 12/7/14 - Pitched the yeast into the starter and put onto the stir plate.  By the evening thick krausen developed.  At some point a bit of it overflowed the top (you can see the dried beer in the picture above).  The starter smells a lot like a budweiser - there is also a slight sulfur smell that I had heard could develop with a lager yeast.  Not a real pleasant smelling fermentation - hope this is largely a product of the warmer temps
•  12/10/14 - Fermentation appeared to have completed so I mixed up another 2 liter starter with 7.5 oz of DME in a pot and chilled the flask in the fridge to drop the yeast.
• 12/11/14 - Decanted off the spent wort and added the new 2 liters of fresh wort and put it back onto the stir plate.  By the evening the starter had popped on me and I lost about a cup of wort onto the floor (big mess)
• 12/12/14 Brew Day - 1:00 PM to 5:15 PM including setup and cleanup
• Heated 10 gal of spring water to 184 F - took 40 min
• Added gypsum and CaCl to the mash tun
• Added 15 qt to the mash tun (I've given up on the 1.25 qt of water to lbs of grain ratio).  Continued to heat the kettle in case the temps came up low
• Let mash tun temps settle for 5 min - ended up at 172 F (was shooting for 169 F) - close enough
• Added grain - stirred to eliminate dough balls.  Ended up at 152 to 154 F
• Added 3 qt of boiling water which initially brought the temperature to between 154 F and 157 F.  Decided not to attempt any further course correction.
• After 30 min the mash temperature was between 157 F and 160 F which was quite a bit higher than the target of 154 F.  Will be interesting to see how this impacts the FG.
• At the end of 60 min the mash temp was at 157 throughout most of the mash
• Stirred in 5.5 gal of mashout water at 210 F - mash temp ended up at 172 F.  This was high enough to stop conversion but not so hot as to pull tannins (hopefully).

• Stirred, vorlaufed, and drained slowly - ended up taking 50 min

• After collecting a couple gal I turned on the heat
• Boil had started by the time 4 gal were collected (after 20 min)
• Added the 60 min hops after collecting 6 gal of wort (after 40 min)
• Ended up collecting 7.25 gal of wort
• Added the 30 min hops once the volume boiled down to 7 gal
• Added the irish moss at 6.5 gal
• Added the 10 min hops at 6.25 gal
• Once the volume got near 6 gal I killed the flame and added the chiller to sanitize and the 0 min hops
• Let the hops steep for ~10 min
• Chilled to ground water temps (~55 F) - took 15 min
• Collected 6 gal of wort.  Avoided transferring most of the hops but got most of the cold break
• Poured back and fourth between two buckets to aerate
• Moved the fermentor to the chest freezer to chill down to 48 F
• Measured the gravity of a sample as 1.054.  It is a nice brown color and fairly clear after sitting for half an hour or so

• Once the fermentor got down to 48 F I put the starter in the chamber to chill down to pitching temps.  I then decanted off most of the starter wort and pitched the yeast

• 12/13/14 - No fermentation activity the next morning - I understand that the lag time for a lager is longer than for an ale due to the cooler temps
• 12/15/14 - Switched from a blow off tube to a 3 piece airlock.  Beer is now bubbling slowly
• 12/27/14 - Increased the fermentation chamber temperature to allow the beer to rise to 65 F for the D rest (this is 1 week earlier than initially planned)
• 1/2/15 - The temperature had risen to 61 F after a week of D-rest time.  Pulled a sample and measured the gravity as 1.020 - expect it to drop a little bit more with the lagering.  It is a pretty nice mahogany color and fairly clear at this point.  The flavor is very clean at this point - no butter/butterscotch or sulpher off-flavors - I'm calling the D-rest complete.  It has a nice balance between sweet malt and hops.  I will lower the temperature by 5 F a day until it is down to lagering temps to try to avoid shocking the yeast.  I will wait to rack to secondary until it is at lagering temp.  Lowered it to 56 F today.

• 1/3/15 - Lowered it to 51 F
• 1/4/15 - Lowered it to 46 F
• 1/5/15 - Lowered it to 41 F
• 1/6/15 - Lowered it to 36 F
• 1/7/15 - Transferred the beer to a better bottle for the secondary lagering period
• 2/18/15 - The beer has spent 6 weeks lagering.  The gravity is still at 1.020 - this is probably due to the slightly hotter than targeted mash temp.  The beer is very clear already but I'm going to fine with gelatin just to make sure (1 tsp dissolved in 1 cup of 160 F tap water).  I will bottle next week.  The beer has a nice clean malty flavor - no off flavors I can detect.
• 2/26/15 - Bottled tonight.  Ended up with 5.25 gal.  Bottled with 6 oz of priming sugar to get ~3.2 vol of carbonation.  Got 54 12 oz bottles from this batch.
• 4/15/15 - Tasting notes - Malty/sweet but still easy drinking beer

Lessons Learned:

1. Putting more than 2 L of wort in a 2 L flask is not a good idea.  I got away with it on the first step of the starter for the most part but for the second step it resulted in a big mess.  Probably would have been better off with a 1.5 L starter of slightly higher gravity for the second step.
2. I had a pretty good time savings from boiling while collecting wort for this batch.  The flow was actually similar to a fly sparge process.
3. I liked that I was able to get decent efficiency from just 10 gal of water.  This made sure that the boil only took 60 min.  I've spent a lot of extra time boiling in my last few batches due to the large sparge volumes.  This extra cost of propane and my time is something that I'd like to analyze more going forward.
4. The more I've brewed here in PA I'm thinking a setup where I can have all my hot side equipment in the garage would save me a lot of time - getting very tired of bringing my stuff up and down the stairs to/from the basement.
5. I think I could get big time savings in the mash from a RIMS setup with a grant and a refractometer to determine if conversion has completed.  I'm mashing for 60 min and not checking conversion - it could be that it's actually complete long before the 60 min.  I also think a refactometer would be really cool for sparging (with a fly sparging setup) as I could stop collecting wort for the boil once I both have sufficient volume and I have collected the correct amount of sugar to meet my OG - this would reduce the boil time and fuel usage.  I really need to move forward with this sort of setup.