Ridiculously Simple Lagering Technique

You don’t even need a fridge!

So you would like to try making a lager, but you're not ideally equipped to do so at the moment. Welcome to the club. By now you have probably researched it extensively on the internet and discovered that brewing a pilsner is a little more complicated than a straight forward pale ale.

Many of us Homebrewers just have the usual dirt simple brew day where we make a total mess of the kitchen, dump the wort in the primary, then leave it in a dark, room temperature place to do it's work. If you live closer to the equator you might be putting the primary in the basement, or wrapping it in a wet towel to make sure the yeast doesn't get to slap happy.

Even during a hot summer, it's possible to pull off a clean tasting ale without to much trouble. Lagers however, present an additional challenge, and it's due to the yeast.

Even if you pitched lager yeast into wort, and fermented as you would an ale, the resulting beer wouldn't be a Lager. It would be an off tasting train wreck because the yeast fermented at temperatures far above the optimum, and didn't have time to condition.

The proper solution is to get a fridge, pull out the racks, and plug it into an external thermostat. In fact two fridges would be ideal so that you could dedicate one to fermentation, and set the other at an even lower temperature for a proper lagering. Who has room for a couple extra fridges though? Well... Many of us if we really put our minds to it... but this article isn't about doing things properly, this article is about cheating.

The hack solution I'm about to offer you can work just as well as a proper beer fridge. All you need is a thermometer, a plastic bucket, a glass carboy, and a lot of luck.

In fact, it might be generous to describe this article as and explanation of an actual technique. It's more of a loose guide to what you might be able to get away with under the right circumstances. They key is recognizing the opportunity when it arrives.

First, lets understand what the yeast is asking for. They want it cold, generally between 9° Celsius and 14° Celsius depending on the strain. Some like it a bit colder, some can go a little warmer. If it's winter the out doors might provide cold enough temperatures, but you don't want to go out one morning in the back yard and find that your beer has frozen solid during a cold snap.

You need a stabilizing counter measure to the sudden changes in temperature outside. That would be your house. There may be spots in your home that are generally colder than others, such as the garage, the basement, or even a closet. Just checking the temperature of the air in that place isn't going to do it though. You need an analogue of your beer.

Take a plastic bucket, fill it with water, and drop a floating dairy thermometer into it. Place the bucket in the coldest part of your home.

Leave It over night. The next morning record the temperature. Check it again around midnight the same day, and make another record. The fallowing morning observe the temperature again.

You will notice that the temperature changes by a few degrees over the span of twenty four hours. If the range of that temperature change is below 16° Celsius and above 7° Celsius and the actual change it's self is only by a few degrees, then you're in business.

Why the bucket/thermometer maneuver? Well a body of liquid will retain heat, and change temperature more slowly than thin air. This will give you a fairly accurate idea of what kind of temperature fluctuations your batch of beer will experience.

A more direct and accurate version of the above test would be to fill a glass carboy with water, and use a battery powered digital thermometer with a temperature probe to take direct readings.

Now, assuming you have had good luck with your lagering location, brew your recipe of choice and cross your fingers. While the beer is fermenting, keep your beer analog (either plastic bucket, or carboy full of water) close by. You can use this device to track the temperature of your beer.

If it's really cold, it might be a good idea to place the fermenter on a wooden block just to be sure that the floor doesn't sap to much heat from the beer.

If the temperature edges to close to the upper limit, wrap the carboy in a wet towel, and leave the bottom end of the towel in a small pail of water. As the towel drys, it will wick more water upwards into the fabric and the continuous evaporation will vent heat from the carboy. If the temperature dips to low, wrap it in something insulating, like blankets, or foam. If it dips really low you may have to move the carboy, but this should be a last resort.

Whether it's a Wyeast, or Whitelabs culture, be sure to check the temperature ratings. Choose a yeast with a wide range that falls well outside your results. Remember that you are trying to set up a relatively long term brew based on some quick and dirty research. In a couple weeks your average temperature results could rise or fall dramatically with the changing of a season. Don't let that stop you though. Remember that you're a Hombrewer. You can do anything, even if you're not doing it properly.

So... Your ferment has been going strong for some time, the temperature issue is well in hand, but what about that second hurtle in the lager process, the actual Lagering part? Lets just bypass a huge area of debate and call this time period "conditioning". It doesn't mater where you draw the line as to what constitutes "primary fermentation", and what separates that from "secondary fermentation".

What's happening during conditioning? Well, compounds produced by the yeast during fermentation are being re-absorbed by the yeast as they fall dormant, and the last remaining volatile flavors are being scrubbed out by the final venting of Co2. Basically you're insuring that your beer tastes like beer rather than unripe apples, popcorn, sulfur, or turnips.

I've tasted all four, and believe me it's worth the wait to avoid the experience. How long do you wait though? Some people condition for a month or more, but two weeks or less is often enough. Even so, this is why you're going to want to go with a glass carboy, as plastic can permit air back into the beer given enough time.

How do you know when to START waiting, in other words, when dose conditioning begin? It begins after the beer reaches Terminal Gravity. This is the point where the yeast has converted almost all of the fermentable sugars into alcohol and Co2, and would rather fall asleep than waste any more time floating around in search one more damn monosaccharide.

Yeast cultures come with an Apparent Attenuation rating. This tells you roughly what percentage of the available sugars will be converted. This factor in conjunction with your original gravity can give you a reasonable idea of when your beer will be done fermenting, and can be considered as entering the conditioning phase.

How do you figure this out? You don't really have to, just assume 75% attenuation.

Your beer will be more or less fermentable, especially if you're going all grain. Unless you did something crazy with crystal malts, this shouldn't be an issue. Assume a nominally fermentable wort. If you can actually figure out the ratio of fermentables to non-fermentables in your wort, you probably don't need to read this article. In fact, feel free to e-mail me and tell me how it's done.

Why is 75% a good figure to assume? Well, it always seams to be in the ball park. Lets say you're using Wyeast 2042 "Danish Lager Yeast", apparent attenuation 73-77%

See, that's close enough to 75%

... What? That's not good enough? You want to at least know what the average attenuation of that specific yeast is?... FINE . To get an average, add the numbers together then divide by the number of numbers: 77 and 73 = 150... There are two numbers, so 150 / 2 = 75.

In truth, the easiest way to do this is to just say no to math, and use your thumb to eye ball 75% of the distance between your OG and 1.000 on your hydrometer. It's literally a rule of thumb.

Assuming you prefer at least a minimal amount of math, how do you turn your original gravity into a projected terminal gravity?

Lets assume that your original gravity is something tricky like 1.043. The first step is to drop the first two digits. You don't need them. The result is 43. Now assume 75% apparent attenuation. Here is the formula:

P = OG - (A X OG)

• P is the projected apparent attenuation, the figure you're after.
• OG is your original gravity.
• A is the average apparent attenuation of the yeast culture, expressed in decimals.

So... 45 - (0.75 X 45) = 11.25. Basically a terminal gravity of 1.011.

By doing this homework, you can know what to look for when you check your gravity towards the end of the ferment. If for some reason the beer ends a little higher or lower then that, It should be apparent that you are apparently attenuated, if a couple days go by and the gravity hasn't dropped any lower. Essentially, If the beer has definitely stopped, then it's time to start waiting. (conditioning)

How long you wait is entirely up to you. Lagering by the seat of your pants really boils down to a mater of taste. My recommendation for your first stab at a lagering is to wait two weeks, then do a taste test.

If the beer still doesn't taste right, leave if for another week, and so on. If a few months go by and it still tastes like ass, don't beat your self up, or become discouraged. Don't ever become discouraged.

I, and my close friend Neil, a fellow Homebewer, once embarked on an epic brew quest. We were resolved to brew the same Danish Pilsner two different ways. We would triple decoct one batch, then do the next as a single infusion. The first decoction was a write off because of a horrific contamination. The second attempt at decoction went perfectly. The single infusion worked out as well.

Both the viable batches tasted badly of acetaldehyde, but otherwise were pretty good. Upon tasting this mixed success, my other close friend Colin, a fellow beer snob, said the following: "Congratulations, you've managed to replicate everything I hate about Pilsners."

I can't think of a higher complement.