Brewing Lager at Home

Posted on 01.01.08 5:30PM under Brewing, Lager

New Year’s Eve in NYCHey, first of all, Happy New Year! Welcome to 2008!

Since this week is Bock week, I decided to make this week’s brewing post about brewing a lager. This will be a learning experience for me, too, so join me.

The only difference between making a lager and making an ale is fermentation. So thinking of brewing as the actual cooking: mashing and boiling, brewing a lager is the same as brewing an ale. At any point before you pitch your yeast, your wort could become a lager or it could become an ale. It all depends on the type of yeast you use and the temperatures you ferment at. This will guide you through the fermentation schedule for a lager.

Lager yeast should be pitched at a much cooler temperature than you would pitch ale yeast. It is strain dependant, but somewhere in the 45-50°F range is appropriate. Some say to pitch warm, to ensure a good start to fermentation, but I would pitch at desired fermentation temperature, just like with an ale. To me, the idea is that you want the yeast to have as consistent an environment for work as possible.

Another important factor for lager yeast is to have a big starter with a high count of healthy yeast. Even though they’re made to work at the lower temperatures, fermentation still is less vigorous at those lower temperatures. If you’ve ever made a Belgian that fermented at 80°F, you’ll know that higher temperature fermentations are a lot more vigorous. Use an online calculator like Mr. Malty, or just make a two or three quart starter for your lager beer. Make sure to ferment the starter at the same temperature you intend to ferment the main beer. Again, yeast don’t like to endure a lot of temperature changes.

Once the main fermentation is done, a Diacetyl rest is recommended, where the beer is put in a warm (60-70°F) environment for a few days. This allows the yeast to get a little more active at the tail end of fermentation, to encourage them to complete their job. It also enables them to do a bit of cleanup work, and remove some of their own unwanted byproducts.

After a few days at the warmer temperature, it’s time to actually lager your lager. Transfer it to glass secondary to get it off the yeast cake, and ensure an oxygen-impermeable lagering environment. To lager the beer, store it at 32°F for several weeks. Six weeks should be a good amount of time. You could probably get by with four weeks, but the longer the better. Taste it along the way if you can safely do so without risking infection, and you’ll be able to tell when it’s ready to package.

Packaging (e.g. bottling) is pretty much the same as with ale. One notable difference is that you will want to add another packet of yeast at bottling time, since all that lagering has stressed the yeast that you had in there. A $2 pack of dry yeast (properly rehydrated) should do the trick. The other surprising fact is that you should just condition your bottles in a warm environment just like you would with an ale.

That sums up the differences between making an ale and making a lager. In order to do this properly, you will need temperature control for a refrigerator or freezer to hold a cool fermentation temperature and make the temperature adjustments for diacetyl rest, lagering, and conditioning. You’ll probably need space that you can dedicate to the specific temperature needs of the lager for a long time. But in the end it will be worth it to add that notch to your belt – to be able to say you made a lager, and have a full range of capabilities in the beer brewing world. Well I guess we didn’t get to spontaneous fermentation and blending gueuze yet, but we’ll get there eventually. In the mean time, make a Collaborator!

Comments are closed.