How Temperature Effects Beer Making
The temperature at which you brew beer is important to the final product. The variations in temperature are needed in order to produce different types of beer. When yeast is used, fermentation takes place with specific temperatures. The use of malt requires certain temperatures and temperature rests (waiting periods) for proper breakdown of the enzymes.
Fermentation is the step of the brewing process where yeast is added to the mixture. At this point the product is called beer. During this stage the sugar from the malt is metabolized and creates alcohol and carbon dioxide. These steps have specific temperature requirements depending on the type of beer that is being brewed. The two main types of beers are ales and lagers. Most other varieties are variations of one of these two.
Ale yeasts ferment at temperatures between 15°C and 20°C (60°F to 68°F), and occasionally as high as 24°C (75°F). Ale yeasts form a foam on the surface of the fermenting beer. This is refered to as top-fermenting yeast. Ale is typically done fermenting in about three weeks. Ale is the most popular variety of beer in England with literally hundreds of varieties available.
Lager yeast collects at the bottom of the fermenter and because of this is often referred to at bottom-fermenting yeast. Lager is fermented at much lower temperatures than ale. It is fermented at about 10°C (50°F), compared to typical ale fermentation temperatures of 18°C (65°F). It is then stored for 30 days or longer at temperatures near freezing. Lager beer becomes mellow and the tastes become smoother during the storing and lagering process. Sulfur develops during the fermentation process but dissipates during storage.
The variations in fermentation produce many varied types of beers and ales. In the years before refrigeration beers were often stored in cellars or basements to ferment because the temperature there was best for the process. Temperature was also a big factor in the types of beers and ales that were produced during the different seasons of the year. The popularity of lager was a contributing factor in the introduction of refrigeration in the early 1900s.
Author: Graham Williams
Article Source: EzineArticles.com
Provided by: Canada duty rate