What is the difference between an ale and a lager?

In the most basic classification scheme, there are two main types of beer. No, its not “tastes great” / ”less filling”- they are ales and lagers. Ales, the oldest beers in the world, have been around thousands of years longer than lagers.

Looking at the history of beer, civilizations as far back as the Sumerians and Egyptians have been brewing and drinking what would be considered ales. Lagers, on the other hand, may have only been around since the mid-nineteenth century. However, many have speculated that “lagering” may have been “discovered” as far back as the Dark Ages, when some European brewers may have stored their beer in ice caves for later consumption. What they found was that the beer that was stored and fermented cold had a much clearer and cleaner beer “free from turbidity”.

The main difference between ales and lagers is the type of yeast used in the brewing process, which in turn dictates what ingredients and techniques can be used.

Ales are fermented warm and made with a top-fermenting yeast (Saccharomyces cervisiae), which is, just like it sounds, a yeast that rises to the top of the brew during fermentation. Ales are generally stronger and more forceful in taste than lagers because of their relatively fast and warm fermentation. Many countries, including England, serve their ales at “cellar” temperature (50-55 degrees Fahrenheit).

Lagers, from the German word “lagern” meaning to store, are made with a bottom or cold-fermenting yeast (Saccharomyces Uvarum – see sidebar) that sinks to the bottom of the brew during the fermentation process. While ales can be brewed in as little as 7 days, lagers traditionally need to age before their brewing process is complete. This can increase their brewing time to more than a month or more. This longer, colder fermentation process inhibits the production of esters (which give beer a more fruity taste) and avoids other fermentation byproducts common in ales. The lager process creates beers with a generally cleaner, smoother, crisper, and more mellow taste. Unlike ales, lagers should always be served cold. The lager is also the most popular style of beer in the world, with some stating that it accounts for 90% of all beers consumed (a large portion of this is from the mass produced watered down lagers of the major US breweries).

Note – Lager yeast (Saccharomyces Uvarum) was originally named Saccharomyces carlsbergensis (notice the word “Carlsberg” in there… not a coincidence). The name was chosen to honor the brewery that was credited with first isolating lager yeast (Carlsberg brewery) – the yeast was later named Saccharomyces Uvarum) Bottom-fermenting yeast was simultaneously discovered by Gabriel Sedlmayr and Anton Dreher about 1830.

Ale vs. Lager – At A Glance

AleLager
Thousands of years oldRelatively new
Fermented warmFermented cold
Top fermentationBottom fermentation
Yeast - Saccharomyces cerevisiaeYeast - Saccharomyces Uvarum
Quick brew cycle - as little as 7 daysLonger brew cycle - up to several months
Usually fermented between 59 - 77 degrees FUsually fermented between 40 and 55 degrees F
Strong, assertive, and more robust in tasteSmoother, crisper, and more subtle in taste and aroma
Served not too cool, usually 50-55 degrees F, 10-14 degrees C, sometimes called "cellar temperature".Served cold, usually 40-45 degrees F, 4-7 degrees C.