What does lager mean?

In a broader sense, the term lager refers to any bottom-fermented beer (as opposed to “ale,” which refers to any top-fermented beer). In this sense, the term “lager” applies to a large group of products, including both light and dark beers, such as pilsner, bock, Märzen and Baltic porter. These beers are fermented using yeast of the species Saccharomyces pastorianus (formerly known as Saccharomyces carlsbergensis).

The term “lager” itself derives from the German verb lagern, which can be translated into English using verbs such as “store,” “stock,” “warehouse,” and also “age.” In reference to alcoholic beverages, the latter means “to be stored for a sufficiently long time under specific conditions in order to acquire the desired properties.” The term “lager” therefore refers to the fact that so-called young beer must spend a specific amount of time under suitable conditions after fermentation to trigger the biochemical and physical processes that shape its desired properties. During aging, the beer becomes clear and its flavor and aroma profile develops, mainly as a result of the breakdown of fermentation by-products. Thus, aging is an attribute of all lagers. In Czech, lager, meaning bottom-fermented beer, is referred to as ležák; light beer is světlý ležák, while dark beer is tmavý ležák.

These beers are produced using yeast of the species Saccharomyces pastorianus, also known as lager yeast or—because it settles to the bottom of the tank once the fermentation process is complete—bottom-fermenting yeast. Lager yeast can break down sugars at low temperatures (the optimal fermentation conditions for this yeast range from 8 to 12 degrees Celsius). As a result, the fermentation process is slower and gentler than in the case of top-fermented beers. Aging also requires low temperatures. In the past, these beers were produced exclusively during the winter months and stored in deep cellars, where the temperature did not exceed a dozen or so degrees Celsius even during the summer heat. Ice was also used to cool them. Therefore, due to the extended fermentation process and the need to maintain a low temperature for a longer period, the mass production of lagers began later than that of traditional top-fermented beers.

When suitable conditions are provided, resulting in the formation of a relatively small amount of fermentation by-products, beers with a clean, neutral flavor and aroma profile are obtained. In these beers, the flavors and aromas of malt and hops are clearly perceptible and are not muted by other flavor and aroma notes. The flavor and aroma of lagers, especially light beers in this group, consist of grain and bread notes derived from the malt, as well as floral, herbal and spicy notes derived from the hops, with the malt and hop accents appearing perfectly balanced and neither dominating the other.

This delicate and balanced beer became the basis for creating the currently most popular beer style, accounting for more than 90 percent of global consumption. This refers to an impeccably clear and refreshing light bottom-fermented beer aimed at the mass market, which colloquially, as a result of an oversimplification that is not entirely justified, began to be called lager (although other terms are also used for this type of beer: light lager, international lager, European lager or eurolager, American lager, American light lager, macro lager, etc.). By design, this beer is intended to meet the expectations of the broadest possible group of consumers. It should be inexpensive, easily available and approachable in flavor. Accordingly, it is produced in enormous quantities (in Poland, several billion liters per year) using a technology known as High-Gravity Brewing (HGB), which involves brewing wort with a higher extract and diluting it before packaging, using or adding cheaper raw materials (e.g. unmalted grains), and it reaches stores quickly (after the introduction of so-called beer conditioning instead of aging).

The economic and political situation in the United States had the greatest influence on the emergence of this beer style, particularly during Prohibition, the so-called Great Depression and World War II. Due to rising raw material prices and limited demand, breweries were forced to drastically reduce production costs. As a result, the amount of hops and malted raw materials used in the brewing process was gradually reduced or eliminated entirely (cheaper substitutes, such as corn and rice, were used instead). When, in the absence of men fighting on the fronts of World War II, efforts were made to encourage women to consume beer in order to expand the market, marketing specialists concluded that they preferred beers with lower bitterness and a less pronounced flavor. In this way, a beer was created that dominated the global market in the following decades.