Mashing for Great Lager
Q: Hi, Matt. I have a question about mash schedules for lagers. When do you see it useful to do a single-infusion versus a step mash versus a decoction mash? —Mo in Denver
MB: I’ve had the great fortune to predominantly work in breweries with mash mixers, so I’ve always had step mashing available to me. So, just about every beer we make involves some type of a step mash. Even if we’re doing the equivalent of a single infusion, we add a mash-off step. But when it comes to lagers, I’ll just tell you straight out what our mash program is, and then we can work around that. So, we actually mash in [for] a protein rest at 122°F (50°C). One, you get to take advantage of proteolytic enzyme activity. There may be some other enzyme activity that’s at work there, but it also allows you the ability to get all in below [saccharification] temperature, and then ramp up and control your complete conversion program—whatever that might be.
Most of the lager we brew these days—even our Oaktoberfest—we want to be pretty dry. And often we’re mashing for maximum fermentability or attenuation. So, we would then ramp up to 145°F (63°C) in our program, and we would adjust the timing there. For Pivo, [for example,] we’re standing at about 45 minutes. And then I like to ramp up to some place north of 155°F (68°C), so that we can finish conversion. What we find with some of the European pilsner malts is that they like an even higher temperature—something closer to 162°F (72°C). And then a final rest, a relatively low mash-off rest. Some might argue it’s not high enough, but we’ve traditionally gone to only about 169–171°F (76–77°C) for our mash-off temperature. To take a step back, we spend 45 minutes at 145°F (63°C). In this particular regimen, we might spend 20 or 30 minutes at the higher saccharification temperature—the alpha-amylase temperature—and then when we get to mash-off, we don’t spend a lot of time at that rest. We’re then dropping to the lauter tun as quickly as we can after that.