Lagers and Ales & Lagered Ales

The Beer

Lagers and Ales & Lagered Ales

Beers generally fall into two specific categories, ales and lagers. The type of beer is dictated by the yeast used to produce it. Ales use top fermenting (obergärig) yeast, while lagers are produced using bottom fermenting (untergärig) yeast.

Once upon a time all beers were ales and all brewing yeasts were ale yeasts. That’s because the science of beer making was not yet fully understood, and most beers were produced by “spontaneous fermentation.” In reality, wild yeasts floating through the air or living on the brewer's wooden paddle got into the wort. Presto, you've got fermentation. As you can imagine, there wasn’t a lot of consistency from batch to batch back then. Eventually, brewers learned to cultivate specific yeast strains that produced the beer qualities they were trying to achieve.

Ale yeasts are considered “top fermenting” yeasts as they tend to produce a rocky head of foam on the beer during fermentation. They are also generally active at warmer temperatures (65 – 75 F) and ferment quicker than lager yeasts. As a result of this fast, warm fermentation, Ales tend to produce more fruity, sweet, complex beers.

Over time, brewers in Europe discovered that beer produced during the cold winter months was different than in the summer (remember, there was no refrigeration back then). The beer took longer to make, but seemed to have a “cleaner”, less fruity flavor profile. The yeast that made this beer was considered bottom fermenting because it didn’t produce the distinctive rocky head that ale yeasts produce. The resulting beer eventually became known as a lager (which means “to store” in German), due to the practice in Europe of using cold storage (underground in caves) to produce lager year round. They controlled the temperature in the fermentation cellars using blocks of ice harvested in the winter. Eventually, with the invention of refrigeration, all aspects of beer production could be controlled precisely.

Lagered ales are somewhat of a hybrid beer. They are technically ales, produced using top fermenting (obergärig) yeast strains. However, over the years in places like Düsseldorf and Cologne, brewers have adapted their yeast to an extended period of cold storage (lagering) following primary fermentation.

This results in a beer that maintains the flavor of an ale, but also exhibits the clean refreshment of a lager. One could argue that lagered ales are truly the best of both worlds.