Ales and Lagers : two different fermentation
Top fermented beers: these are beers brewed at higher temperatures, ranging between 15 and 25° c. The term "high" refers not only to the temperature range in which yeasts (Saccharomyces cerevisiae) are particularly active, but also to the fact that during fermentation on the surface of the liquid forms a thick layer of foam due to the strong rising carbon dioxide and metabolic wastes. It is in this way that were produced in ancient times, before the bottom-fermented beers took hold.
Bottom-fermented beers: Unlike earlier, for the production of these beers using yeasts whose optimal temperature range is around 8-10° c. Exactly in reverse of top fermentation, in this case the yeasts (e.g. Saccharomyces pastorianus) settle all at the bottom of the liquid at the end of the process It is estimated that currently the vast majority of the beers produced worldwide (approximately 90%) are bottom-fermented. And this explains the difference between Ale and Lager: while the former are top fermented, the birreLager are bottom-fermented. In the latter case, the process can take anywhere from one to three months; below are the times in the case of top-fermenting beers.
The bottom-fermented beers
The Ales were the first to be produced, because they were ' simply ' ferment the ingredients at room temperature. However these beers were characterized by a certain instability due to thermal shock, so it began storing beer in very cold places, such as the caves of mountain areas. It turned out that way, quite casually, that beers kept at low temperatures were more stable because the yeasts are deposited on the bottom of the containers. Continuing to adopt these techniques over time, there was a natural selection which eliminated top-fermenting yeasts for giving way to those best tolerant of low temperatures. And by this process of "lagerung" (which in German means ' deposit ', ' storage ') yielded the first Lager beers.
Main characteristics, flavors and taste of Lager and Ale
As for the production of Lager yeasts work at temperatures a few degrees centigrade, it is inevitable that their metabolism is not as active as that of microorganisms used in top fermentation. It is for this reason that the Lager have a low alcohol content, and their taste is less fruity, aromatic and quaint compared to beer Ale. Because of their characteristics so peculiar, Lager and Ale go drinking at different temperatures if you want to fully appreciate their flavors and scents: very cold Lager (4-6° C) above the wings (about 10° C).
What's the best style?
Up to you and to your taste!