To the casual sipper of suds, there are only two types of beer: The kind you like and the kind you don’t. Am I right? But have you ever asked yourself why a lager is a lager and why ale is ale? Chances are you haven’t really thought about it too much.
Today, mass-market golden pale beers are called lagers or pilsners. You know, like that one beer “brewed the hard way,” with Clydesdales in its commercials. Lagers and pilsners are like Coca-Cola to Pepsi. They’re quite similar, with pilsner sometimes being a more “hop forward” pale version of lager.
The world’s first pale lager was brewed in 1842; ale is much older and basically covers everything else not marketed as a lager. Think IPA or stouts. Some might believe the color of beer determines if it is a lager or ale. It does not. Nor does the alcohol content.
So, what’s the difference? Yeast.
You can’t make beer without yeast. And it’s the yeast that determines if you’re drinking a lager or ale. Every style of beer falls under one of these two types.
Ales are typically fermented using what’s considered top-fermenting yeast — Saccharomyces cerevisiae. The name “Saccharomyces” derives from Latinized Greek, which translates to “sugar-fungus.” “Cerevisiae” is Latin, meaning “of beer,” and this type of yeast has been around since ancient times. Saccharomyces is also commonly used in winemaking and bread-baking.
When brewing with Saccharomyces cerevisiae, fermentation happens at warmer temperatures, causing a layer of krausen (pronounced kroy-ZEN) to rise to the top of the fermentation vessel. This krausen looks like a cloud of foam resting on top of the liquid. Fermenting yeast at higher temperatures produces unique characteristics, such as perceived fruit flavors and aromas, and makes for a more complex beer profile.
Lager is fermented using what many refer to as bottom-fermenting yeast — Saccharomyces pastorianus, named after famous French microbiologist Louis Pasteur. This strain works best at colder temperatures. Once fermented, the beer is then lagered at just above freezing temperatures for a prolonged period of time. This method of cold conditioning allows unwanted proteins and haze to drop out of the beer. The result is a clean, bright finish. Typically these lagers are light-bodied, which is especially true in mass-market lagers that use adjuncts like rice or corn in the recipe.
For homebrewers wanting to brew a lager, you’ll need to control your fermentation temperature. You can convert a chest freezer or mini fridge using a dual-stage temperature controller and a heat source (an infrared reptile heat bulb works). A temperature controller overrides the internal settings of the cooler, allowing you to raise or lower temperatures. The temperature controller triggers the heat source if the cooler gets too cold, and switches on the cooling system if it gets too warm. Control your temps and you’ll be making a lager in no time.
A brief lesson on the word “lager”
With traces of brewing dating back centuries, Germany (Bavaria, if you’re hip) is arguably the world’s foremost influence on beer, and the word “lager” derives from the German word lagern, meaning “to store.”
Prior to the invention of refrigeration, brewers would lager next to cold bodies of water in the winter and use ice blocks to hold down temps. During the summer season, it was not uncommon for brewers to store beer in ice caves as a way to lager — a technique dating back to the Middle Ages. The lengthy lagering process resulted in a much cleaner beer, and the process was typical for all beers brewed.
Sometime in the 19th century, Bavarian brewers began experimenting with storing beer in cold cellars for prolonged periods. After the first stage of fermentation was complete, brewers would store the beer at a temperature right above freezing for the lagering process.
As more Germans immigrated to the United States during the 19th century, brewers brought their unique brewing practices with them. It’s during this time that the method of lagering became popular in the new world. But the German influence didn’t stop there. By the end of World War I, the practices of lagering spread throughout Mexico, South America and Asia and have since become the most popular beers worldwide.