At Heater Allen Brewing we concentrate on producing German and Czech style lager beers. In a country where most craft beers are ales and most lagers are made by large corporations, we often end up explaining to people what exactly a lager beer is. There are three main differences between a lager beer and an ale, and these three differences all revolve around an ingredient, the yeast. Lagers are made with the yeast genus Saccharomyces pastorianus, ales are made with Saccharomyces cerevisiae.
The first difference between these yeast strains is temperature. Lager yeast can effectively ferment beer between 40-55° F (4-13°C), and is still active at temperatures close to freezing. Ales prefer temperatures around 60-75° F (15-24°C) and will go dormant at too cold of a temperature.
Because of these cold temperatures lager yeast like to ferment at we arrive at our second divergence, time. Lagers, generally, take longer to ferment. Some ale strains can finish fermentation in just a few days whereas most lagers take around two weeks, sometimes longer, to complete fermentation. It should also be noted that lager in German means "to store," which usually means that after a lager is finished with fermentation it will be put in a tank where it will sit until the brewer deems it acceptable to drink. Of course, ales can be stored and aged as well, but it is not always a part of production.
Our final variation has to do with flavor. A lager yeast will not (or at least shouldn't) add any flavors or aromas to a beer whereas an ale yeast often does add pleasant aromas and flavors to a beer, these are often refered to as esters. That cold, long fermentation allows the lager yeast to clean up these esters resulting in a cleaner, crisper tasting beer. Lagers can be any color, they can be bitter or mellow, but they are usually more malt driven and cleaner tasting then ales.
Our beers spend at least two weeks in fermenter and then are lagered least four weeks - some more (some a lot more!). All of our beers are unfiltered, however, we go through measures to release the beer when most of the yeast has dropped out and the beer is as clear as possible. This still means that depending on how the beer is stored it may throw a slight haze from time to time; we recommend storing our cans upright and pouring slowly to reduce the haze possibility.