Poor attenuation. Munich malt?

I made a Baltic Porter 1.080, it attenuated only 60%, to 1.036. I tried to push it lower: 6 weeks of primary, rousing the yeast, increasing temp to 70F, I even pitched new starter (Cali Ale) - new yeast worked some 10 days, airlock was bubblig, but FG didn't change.

I can yet dump the beer on a fresh Cali Ale yeast cake, but is it worth it?

Most of the grist was Weyermann Munich Malt II, mashed in 152F. I've heard it is not very fermentable grain...

Piotr said:

Most of the grist was Weyermann Munich Malt II, mashed in 152F. I've heard it is not very fermentable grain...

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It’s as fermentable as other grains, but it is more deficient in enzymatic power. I had a similar experience with the BestMalz dark Munich. W/o special treatment this malt would produce very unfermentable worts. I ended up using a decoction where I decocted most of the grain and held the sacc rest around 60C (140F) This gave me sufficient beta amylase and limit dextrinase activity to reach the desired attenuation potential of 77%.

W/o decoction I would use a very long (45-60 min) rest at 63C and another rest at 70C for 30-45 min. Or add 20% Pilsner or pale malt to bump up the enzymes.

Kai

I've only used Munich I, and I've never noticed a problem with attenuation. Then again I've never used it in a beer with quite so high an OG. I've gone up to 1.07 or so in a 50/50 Munich I/Vienna beer and that attentuated fine.

The depth of knowledge here is ridiculous. Kai's response finally convinced me to sign up for one of those expanded membership thingies.

dogbar said:

The depth of knowledge here is ridiculous. Kai's response finally convinced me to sign up for one of those expanded membership thingies.

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It is impressive. Kaiser is the resident über-beer geek though, the rest of us are just wanna-be's.

Yeah defiantly going to have to upgrade when a few bucks find themselves free, as a newb I've gotta say some of kaiser's posts make my head spin more than a high grav brew...

Kaiser said:

It’s as fermentable as other grains, but it is more deficient in enzymatic power. I had a similar experience with the BestMalz dark Munich. W/o special treatment this malt would produce very unfermentable worts. I ended up using a decoction where I decocted most of the grain and held the sacc rest around 60C (140F) This gave me sufficient beta amylase and limit dextrinase activity to reach the desired attenuation potential of 77%.

W/o decoction I would use a very long (45-60 min) rest at 63C and another rest at 70C for 30-45 min. Or add 20% Pilsner or pale malt to bump up the enzymes.

Kai

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What scares me, is that I sort of understand this

I'm taking it this was a PM? If so, you could also add either some amylase enzyme or add some pils or pale malt to your PM.

Dark Munich has very little diastatic power, especially the beta amylase. Simular to what Like Kai said, you could PM them at 140 and rest long.

Did you have any other grains in your PM? Crystal malts will also lower attenuation %.

Finally I made a doppelbock that attenuated properly from 19 Plato to 5 Plato (6 kg munich II, 2 kg pils, 0.9 kg Caramunich III), but I had to use many tricks to achieve that goal:

- mashing for most fermentable wort : 62C - 50', 65C - 30', 72C - 10'
- lots of healthy yeast: I dumped the wort on a fresh yeast cake, even without washing the yeast
- I added a couple of grams of yeast nutrient
- at the end of fermentation (4 weeks total) I rised temperature to 18C

OH, OK you are doing AG. Yeah the pils helps. Glad it worked out!

Speaking of dark munich. I'm tempted to make a SMaSH with Gambrinus honey malt, amylase to convert and columbus hops for bittering and flavor. Need the amylase and the columbus though.

I find the honey malt to almost be like concentrated munich.

It's nice to see a brewer post in metric for a change. I get tired of doing the conversions all the time!