Beer can be categorized by many factors such as color, flavor, ingredients, strength, brewing methods, origin, etc. In this page, you will find some basic, yet essential knowledge of beer styles for quick reference. Take a look at the periodic table below to get a general idea of the broad spectrum and variety of the many different styles of beer. Then we will explore each factor that contributes to the composition of beer.
We have to first define some basic terms and concepts to read this table. Several typical elements are used to study a beer's style such as aroma, appearance, flavor, mouthfeel and strength.
There are two main types of beer: Ales (Group I - IX) and Lagers (Group X - XIII), and a less common one: hybrid (Group XIV - XX) which is located on the right bottom corner of the table. The difference between Ales and Lagers is due to the type of yeast used during fermentation. Ale yeasts thrive between 62 to 75 degrees Fahrenheit and fluctuate at the top of the fermentation vessel. Lager yeasts prefer lower temperatures, typically 38 to 58 degrees Fahrenheit, and remain closer to the bottom of the vessel. However, there are versatile yeast strains that can perform fermentation at ale and lager temperatures, usually between 58 and 64 degrees Fahrenheit. It is typical that Ales have lighter color than Lagers, but not all the case. Ales and Lagers can be both further divided into sub-groups. Refer to the periodic table for further details of sub-groups.
Now let's take a look at the example key on the left bottom corner. "Geuze" is the name of the style. It belongs to Group II (Lambics and sours) that falls in the category of Ales. SRM (Standard Reference Method) value is 4-15, which is relatively small, indicating a light color. The small IBU value, 5-15, suggests a sweet and less bitter mouthfeel compared to the groups of the right side of the table. Alcohol content is 4.7%-6.4%, which we can read from the ABV (Alcohol by Volume) value. Original Gravity or OG (1.044-1.056) is measured using a hydrometer the instant before the yeast is added to the chilled wort (unfermented beer) after the boiling process. This reading more or less shows the density of the wort and the amount of sugars pulled from the malt. For instance, tap water should read 1.000. The Final Gravity or FG ( 1.006-1.012) is measured at the end of fermentation, thus determining how effectively the yeast consumed the sugars. Measurements of OG and FG are used to calculate ABV using this formula: OG-FG x 131.25 = ABV
Now you can understand all the beer styles in the table and compare them. Just from the name, you will have some sense of what it should taste like.