To beer or not to beer; for many that is never a question. Of the more than ninety different types of beer in the world, two of the most popular are ales and lagers. One of the most-asked questions for many beer drinkers is, "What is the difference between lagers and ales?" There are several factors that distinguish these two beloved beers.
History
The histories of ale and lager are quite different. Ale is the oldest of the two. The first version of this drink dates back to ancient Egyptian and Sumerian times. Lager is estimated to have been introduced around the 19th century. There are theories that lagers have existed for far longer than previously thought. Research has found that during the Dark Ages a lager type of drink was stored in ice caves in Europe. The brewers found that this created a purer version of the beer.
Fermentation process
The fermentation processes of ale and lager are vastly different. They use different versions of yeast. Ales use a yeast called Saccharomyces cerevisiae. Lagers use a lager yeast that is much more fragile than its ale counterpart, called Saccharomyces uvarum.
During the ebullition period with ales, top fermentation is utilized. In the fermentation process for ale, a warmer temperature is needed, ranging from 55 to 70 degrees Fahrenheit or 12 to 21 degrees Celsius. With lagers the temperature is much cooler: 38 to 50 degrees Fahrenheit or 3 to 10 degrees Celsius. The temperature difference is a main contributor to the flavor and presentation of the final product.
Ale requires little brewing time. A completed batch can be brewed in as little as seven days. To completely finish a batch of lager can take as much as a month, if not longer. This long aging process is called lagering.
Taste
The completed batches of ale and lager offer their own savors and flavors. Ale represents a more fruity tone. Some find there are notes of green apple and berries, to name a few. It also provides a more aromatic drink than the lager. This is accredited to the warmer temperature during the fermentation process. The temperature also makes the ale more bitter than the lager. On the other hand, the lager provides a light, crisp, smooth and mellow beer. The colder and longer fermentation process prohibits the lager from tasting fruity. Many find lagers to have more of a malt and bread-like flavor.
The ideal temperature for a premium lager is considered to be 42 to 48 degrees Fahrenheit, or 6 to 9 degrees Celsius. In contrast, ale should be served at a warmer temperature, between 44 and 52 degrees Fahrenheit, or 7 to 11 degrees Celsius.
Though there are many different varieties of beer, the lager remains king; of all beer consumed, 90 percent is lager. The ale family of beer continues to create new versions of itself. One of the most popular is the India Pale Ale, better known as IPA. Whichever direction one chooses to go, there are many versions of both lager and ale. And both are worthy of enjoyment.
-Resource: http://www.dummies.com/how-to/content/the-differences-between-ales-and-lagers.html
-Resource: http://www.beer-faq.com/difference-ale-lager/
-Resource: http://allaboutbeer.com/article/lager-beer-vs-ale-beer-does-it-matter/