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Process and fermentation advice for first lager brew (Munich Dunkel)

brian_muz

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I?m looking to brew my first lager on the weekend. I had a smashing Munich Dunkel at Stomping Ground the other day and it?s inspired me to try the style myself. Looking around I?ve decided to go with this recipe from BYO.com:

https://byo.com/article/munich-dunkel-the-original-brown-lager-of-bavaria/

A couple of questions for this brew:

The recipe calls for a step mash. My understanding from various blogs and podcasts is that modern malt is so highly modified these days that step mashing really isn't necessary. I?m thinking of just doing at single sac rest at 65.5C for 60 mins followed by a mash out at 76C. I shouldn?t have any issues with this right? Beersmith indicates the OG will be exactly the same
I notice the Melanoidin and Carafa II are added when I add the mash out water. I haven?t seen or done this before. What?s the theory here?
I?ve had to sub the yeast as LHBS doesn?t stock any of the suggested variety?s. I?m thinking Wyeast Munich Lager 2308 should be a good sub. Any differences here or things I should know about this yeast?
Finally, since I?ve never fermented a lager before, how should I approach fermentation temps? I was thinking a couple of weeks at the recommended temp on the back of the packet, diacyl rest for three days at (?) degrees higher then (?) weeks lagering at (?) degrees then transfer to keg for carbonation. Any helps with how to approach this would be awesome.

Thanks in advance for your advice
 
Doing a step mash or decoction mash is a more traditional approach.  Honestly, I could not tell the difference between beers I have done with a step mash versus single infusion. So that makes it a matter of personal preference in how you want to operate your process.  I see a bit more extraction from doing a step mash, but it is not enough to justify the time I want to spend with the different mash steps.  BeerSmith is not a good indicator of any differences in process as it is a model driven by the user input of brew house efficiency.  Without actually doing the process and noting any differences in the software, you cannot rely on it to accurately predict a change in process.

The late addition of melanoidin and carafa malts fall into the same decision making process as the step mashing.  The theory is that mashing the specialty malts may extract more of the harsher roasted malt flavors and that by capping the mash with them instead of having them in for the full mash.  Again, this is a personal preference in how you want to manage your process.  I have not tried capping or steeping darker malts separately, but I have heard from others that it does produce a smoother less harsh, or less astringent roast flavor at the expense of less extraction and lighter color.  Several people have upped the amount of roasted malts when steeping or capping them to get the same color and noted that this then makes the flavor indistinguishable from just straight mashing the specialty malts.

The other aspect of capping the the specialty malts is easier mash pH control.  Roasted malts and other specialty malts tend to drive the mash pH down, so it takes a little more care to manage the mash pH.  With BeerSmith, I can adjust the amount of acid or add Sodium bicarbonate to the water before the mash to compensate for the drop in mash pH caused by the more acidic specialty malts.  Again, this comes down to personal preference in how you want to brew.

On to the yeast selection.  WY2308 is perfectly fine for a Dunkel.  I have never used the HellaBock lager strain, so I cannot compare the flavor profiles, but the attenuation and flocculation characteristics of the WY2487 are the same as the WY2308 and both are recommended for Dunkels. 

I ferment most lagers starting at 10C and after the first 4 or 5 days bring the temperature up slowly to around 18C over the course of around a week (basically about 1C rise a day).  I let it stand at 18C for 3 to 4 days to finish out and then cold crash it to around 1C to 3C taking several days to get there.  I hold it there for 5 days to a week before allowing it to come back up to 10C.  From there, I either bottle it and then lager, or I have lagered the carboy in my cold storage (if it is winter) and then bottled.  Since you are kegging, you don't need to worry about suspended yeast for refermentation in the bottle, so you can spend as much time as you want in the carboy or lager it in your keg easily enough.

There are also some quicker lager fermentation profiles out there (and some longer ones).  Much depends upon what you have for temperature controls and space available. 



 
In regards to step/decoction, they do introduce some intricacies as compared to single infusion. Better/quicker clarity, efficiency, different "maltiness".

But, before you tackle that, I'd brew it with a single infusion and focus on fermentation and temperature control/ Those two things are far more important.

Cheers,

Mark
 
If you have the means to ferment at traditional lager temperatures then by all means give it a go. If not however there has been a lot written up lately on warm fermented lagers. Brulosophy has done many experiments with lager fermentation temperatures and different yeasts. Search their Exbeeriments section and you will find at least a dozen such write ups. http://brulosophy.com/projects/exbeeriments/
 
Thanks all for your replies. This is really helpful. I think I'll go with a single infusion mash for my first brew of this beer. I will keep the dark grains until mash out though as this seems easy enough to do.

Good advice on the change this makes to the Ph. I would have missed this. I guess I need to use BS to work out what the mash Ph will be with these grains held back. I typically use BS to predict how much phosphoric acid to add at the start of the mash and then confirm actual Ph with my Ph meter at 15 mins. I usually go with 80% of what BS recommends as predicting Ph seems to be a ballpark figure and I've lowered it too much a few times.

I was pretty sure the yeast would be good as it is recommended for Munich Dunkels. Just wanted to see if there was going to be much flavour difference due to the sub or anything I needed to take into consideration.

I really like the suggested fermentation approach and I'm going to follow it. I have a temp controlled fermentation fridge and a heat belt for for my Brew Bucket. It's spring here in Australia and temps in my garage will go from about 13C (55F) overnight to 28C (82F) during the day so temp control is a must.

Thanks again. Really appreciate it.
 
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