I am going to stick my head above the parapet and write what might be perceived as a contentious article. You see it is my honest opinion that unless you have the right equipment home brew lager is just not possible. Why do I hold this opinion? To better explain my position it is perhaps worth asking the question – what is lager?
Lager is possibly one of the most widely misunderstood beer types. I will illustrate this point with a personal story. Many years ago I celebrated my stag night, well okay let’s call it what it really was a stag weekend, in Munich. I am a brewer and I had some brewing friends who were studying at Wienhenstephan, the famous German brewing university. So it seemed like a good idea to catch up with some old friends and have a celebratory beer based weekend to see out my last few days as a bachelor. We went to one of the famous bierkellers in central Munich and one of my friends, he was an Australian so perhaps could be excused, asked for a lager. Queue embarrassed silence from my German brewer friends and the poor waiter who tried to explain in broken English that wouldn’t he rather have a German beer. What my friend wanted, and the waiter knew this, was a Pilsner style lager beer. So why would you want a Czech beer in the brewing capital of Germany? Once we had explained that he was Australian the waiter promptly poured a Pils and moved on!
So what do we mean by lager?
For most of the beer drinking public, when they are talking about lager, they are referring to a Pilsner style beer. A Pilsner is a crystal clear straw yellow coloured beer with spicy fragrant hop notes and rich malty and grainy flavours. But in reality you can get lager style beers in a variety of colours alcoholic strengths and flavours. I would suggest that lager is not a style of beer but a unique production technique that gives rise to beers with particular flavour characteristics. Lager is derived from the German word lagern which roughly translates as “to store” and comes from the practice of brewing beer in the winter because it was too hot to brew in the summer. The beer brewed therefore was fermented at cold temperatures and stored in cold caves for drinking throughout the year. Fermenting at cooler temperatures led to a beer with more malty flavour notes because the lower fermentation temperature resulted in reduced ester and higher alcohol production by the yeast. But the brewers also found that storing the beer at cold temperatures for a prolonged period greatly improved the quality of the beer. However, the process of lagering beer was made significantly easier with the invention of refrigeration. With refrigeration brewers were able to brew all year round and gain greater control of the consistency of the beer that they brewed.
Sadly, for us home brewers, this is where we encounter our biggest problem if we want to make home brew lager. If we want to make home brew lager style beers we need refrigeration. Typically modern lager style beers are fermented at temperatures anywhere between 11ºC to 15ºC and lagered or cold stored at as low a temperature as possible without the beer freezing. In some cases the lagering temperature can be below zero. As for storage time this can vary but in some cases lager is stored for periods of up to several months. Now this is going to be difficult for most home brewers to achieve. However, do not despair as I think it is possible to brew a reasonable approximation to a lager style beer with normal fermentation temperatures of 18ºC to 22ºC as long as you can cold store for a period of time. The way that I achieve this is by carrying out fermentation at a temperature of around 20ºC. Once primary fermentation is complete I transfer the beer into a secondary fermenter, being careful not to disturb any of the yeast sediment, and place this into an old fridge which I have set to as low a temperature as possible. I have found that, although a bit fruitier than a typical lager, the beers that I have produced in this way have been very good. I would even go as far as to suggest that they could be loosely defined as home brew lager.