As you’ll recall from the “What beer is made from” series, beer is made from four main ingredients – malt, water, yeast and hops.
Simply by varying their choices for each of these ingredients, brewers can create over 100 different beer styles.
So what exactly is a beer style?
When we talked about yeast, we introduced the concept of beer’s 3 families – ale, lager, and mixed fermentation.
Beyond family is style.
Both Irish stout and Belgian witbier are members of the ale family, meaning they’re both brewed with ale yeast. But the malt and hops used in each brew are different – so the expected flavours will differ, too – making Irish stout and Belgian witbier two unique beer styles.
Beer style guidelines are a set of characteristics that allow the brewer to tell the drinker what to expect from a beer in terms of its appearance, aroma, taste, texture and strength. Essentially, they help us to distinguish one beer from another.
But it’s important to remember that they’re simply guidelines, not absolutes.
Not every beer fits a style and not every brewer brews to style – in fact, some brewers actively push the boundaries, occasionally developing new styles in the process!
Plus, styles change over time. Some styles arose in certain places because of the ingredients or equipment available there, but as new ingredients became available or as our understanding of the brewing process improved, the styles evolved. Other factors like technology, changing consumer preference, international influence, regulations, war and more have all had an impact.
I think Randy Mosher, author of Tasting Beer, says it best: “Styles honour the past and give order to the present.”
Who actually ‘defines’ each style?
There are two main organisations that help shape beer’s style guidelines.
The first is the Beer Judge Certification Program (BJCP). This organisation was created by homebrewers in the United States who were looking to categorize and classify the beers they brewed for competitions. They introduced their first set of style guidelines in 1997, defining dozens of beer styles and grouping them by similar production methods, ingredients or flavours.
The BJCP’s Style Guidelines are largely seen as the reference for beer styles today. Not only are they used in judging homebrewing competitions, they’re also referenced when studying for beer certifications offered through the Cicerone® Certification Program. Recognising that styles change over time, the BJCP’s Style Guidelines are reviewed and revised every few years. The last revision took place in 2015.
The second organisation is the United States Brewers Association (BA), the trade association for small and independent craft brewers in the US, who use their style guidelines as the basis for their competitions: the Great American Beer Festival and World Beer Cup.
The BA’s Style Guidelines are reviewed and revised yearly. While that makes the BA guidelines more difficult to study from, as they are continually changing, they’re very helpful for tracking trends and seeing when new beer styles are “officially” recognized for judging. For example, the “Imperial or Double India Pale Ale” was first introduced as a category in 2003, while “Juicy or Hazy India Pale Ale” was a much more recent introduction in 2018.
How does each style differ?
When it comes assessing the differences between beer styles, we can of course talk about each style’s expected appearance, aroma, taste and texture, which we learned how to assess in the “How to taste beer” series.
But there are a few other parameters to introduce that also help set different styles apart: ABV, IBU and SRM.
I promise I’m not speaking in code! Let’s make sense of each of these acronyms one-by-one.
First up, ABV: aka Alcohol by Volume
As yeast ferments sugar, it produces alcohol, the main byproduct of fermentation.
And there are two ways to express the alcohol content of a beer:
- Alcohol as a percent by weight (ABW), and
- Alcohol as a percent by volume (ABV)
ABW used to be the standard measure in the US from 1933 – 1990, as it’s typically a lower number than ABV (3.2% ABW = 4% ABV) and, post-Prohibition, the lower the number the better!
But, ABV is now the international standard.
It translates to the percentage, by volume, of the liquid that is ethanol – so a pint of 5% abv beer means that 5% of the volume of liquid in that glass is alcohol or ethanol.
Each beer style will have an expected ABV range, according to its style guidelines.
IBU: International Bitterness Units
When we introduced hops in the “What beer is made from series”, we mentioned that hops bring beer bitterness, aroma and flavour.
In order for hops to impart their bitterness though, they need to be boiled.
Why? Their bittering alpha acids don’t dissolve particularly well. But during the boil, a structural change takes place, forming iso-alpha acids, which can dissolve into beer.
By taking a measure of a beer’s dissolved iso-alpha acid content, we can measure its bitterness on a scale called IBU or International Bitterness Units. IBU are measured in milligrams per litre, also known as parts per million.
Beers range from approximately 5 IBUs to well over 100 IBUs. (You may see numbers above 100 IBUs, but they’re technically beyond our taste threshold. We can’t actually taste the difference between 100 and 130 IBUs; but we certainly can between 30 and 100 IBUs!)
Styles like American lager and Belgian witbier have less than 20 IBUs; an American pale ale has between 30 – 50 IBUs; and IBUs are highest in styles like double IPA or American barleywine, which range from 50 – 100+.
But it’s important to remember to remember that IBU is a measure of a beer’s bitterness alone… which may not accurately represent the amount of bitterness we actually taste in a beer.
Expected vs. Observed: Perceived Bitterness
Why don’t IBUs tell the full story?
They don’t account for a beer’s sweetness, alcohol content, or carbonation level, which can impact the perception of bitterness, either decreasing it or increasing it:
- Carbonation increases the perception of bitterness
- While intense characteristics – rich malt flavours or high alcohol content – can mask some of the bitterness
A German pils with 40 IBUs might taste assertively bitter, while an English barleywine with 40 IBUs might only exhibit moderate bitterness due to significant levels of alcohol and residual sweetness, for example.
As a general rule, bitterness tastes stronger in a weaker beer.
SRM: Standard Reference Method (or how we talk about beer colour)
Our final parameter has to do with beer’s appearance.
Why measure beer colour? Because each different beer style will have an expected colour range, based on the ingredients that are used in the brew.
Beer colour can be measured on one of two scales: the SRM scale, which stands for Standard Reference Method and ranges in colour from 2 to 40; or EBC (European Brewery Convention), which is approximately twice the SRM value.
There is no single agreed upon verbal description of beer colour, but generally accepted terms range from straw (2-4), to gold (5-9), amber (10-18), brown (19-30) and black (31+). (Numbers in parentheses are approximations from the SRM scale.)
In sum: The key characteristics
So, there you have it!
Each beer style* will be defined by a set of guidelines that:
1. detail the characteristic ingredients used in the brew, and
2. describe the beer’s expected:
- Finish/ Aftertaste
- ABV range
- IBU range and perceived bitterness level, and
- SRM range
Pretty comprehensive, huh?!
Plus, you’ll get learn the history of the style’s development and evolution, how it compares to similar styles, and a list of commercial examples made from breweries around the world so you can give each style a go.
Now that you know what makes a beer style… get ready to start getting to know them!
Check back soon for our first set of style descriptions, featuring classic British & Irish beer styles.
*As defined by the Beer Judge Certification Program