What’s the difference between a lager and a beer?

Answered by Louis Krause

As a sommelier and brewer, I have had the opportunity to delve into the world of beers and explore the differences between various styles. When it comes to lagers and ales, the distinction lies primarily in the fermentation process, which ultimately affects the flavor profiles and characteristics of the final product.

Lagers, in their essence, are beers that undergo a slow fermentation process at low temperatures. The term “” actually derives from the German word “lagern,” which means “to store.” This slow fermentation occurs typically between 45-55 degrees Fahrenheit (7-13 degrees Celsius) and is facilitated by specific strains of known as lager yeast or Saccharomyces pastorianus. This yeast settles at the bottom of the fermentation vessel, hence the term “bottom-fermenting.”

Traditionally, lagers are brewed using a method called “cold conditioning,” where the is stored at near-freezing temperatures for several weeks or even months. This extended period of aging allows the flavors to mellow out and the beer to become smoother. Lagers are known for their crisp, clean, and refreshing characteristics, with a lighter to medium body and a subtle, restrained flavor profile.

On the other hand, ales are brewed using a different strain of yeast known as yeast or Saccharomyces cerevisiae. These yeasts ferment at warmer temperatures, typically between 60-70 degrees Fahrenheit (15-21 degrees Celsius), and rise to the top of the fermentation vessel during the process, hence the term “top-fermenting.” This top-fermentation leads to a faster fermentation process compared to lagers.

Ales are generally brewed in a warmer environment, which allows for a quicker turnaround time in production. This style of beer is known for its wide range of flavors and aromas, often showcasing fruity, floral, and even spicy notes. Ales tend to have a fuller body and a more pronounced bitterness compared to lagers.

It is important to note that while lagers and ales have distinct characteristics, the lines between the two styles have become increasingly blurred in practices. Brewers now experiment with different yeast strains, fermentation temperatures, and aging techniques, resulting in a wide array of hybrid styles that combine elements of both lagers and ales.

Moreover, the term “beer” itself is a broad category that encompasses both lagers and ales, as well as other variations such as stouts, porters, and wheat beers. Each of these styles has its own unique brewing process, ingredients, and flavor profiles, contributing to the vast diversity within the world of beer.

The difference between a lager and a beer lies primarily in the fermentation process and the yeast used. Lagers ferment slowly at low temperatures with bottom-fermenting yeast, resulting in a clean and crisp beer, while ales ferment more quickly at higher temperatures with top-fermenting yeast, leading to a broader range of flavors and aromas. However, it is essential to recognize that the boundaries between these styles have become increasingly blurred, allowing for innovation and the creation of unique hybrid beers.