by Alain Schepers Blogger at Bierista.nl 02 May 2021
What is IBU in beer?And other figures like EBC, Cat. and Alc %?
Beer and figures: probably not a combination to get really excited about. But if you have an insight into figures, you can understand your beers better and really ‘read’ them, even before the bottle is opened. Here we present an explanation of the key figures, which are inseparable from the beer.
Beer IBU: Bitterness
You can measure the bitterness of a beer, in most cases this is measured in IBUs. IBU stands for International Bitterness Unit. The bitterness in beer can come from a variety of different sources, such as herbs or roasted malt. IBUs only show the bitterness of the hops, derived from the alpha acids they contain. These alpha acids can be measured; each milligram of alpha acid per litre of beer is an IBU point.
The IBU value does give an indication of the bitterness of a beer. However, it is important to remember that this doesn’t mean a 50 IBU beer will necessarily taste more bitter than a 40 IBU beer. The way we experience bitterness is also influenced by the amount of carbonic acid, the temperature of the beer and the use of herbs.
- Up to 15 IBU: slightly bitter beers. Examples are Blanche De Namur and Jopen Malle Babbe.
- 15 – 50 IBU: medium bitter, for example Budweiser Budvar Original (22 IBU) and 't IJ Columbus (41 IBU).
- 50 – 70 IBU: bitter to strong bitter beers, such as Hop met de Gijt (60 IBU) and Fourpure Deucebox Double Citrus IPA (70 IBU).
- 70 IBU and above: sometimes it seems that there are no limits on the number of IBUs. Some more extreme examples are Stone Brewing Stone Ruination (100 IBU), De Molen Hemel & Aarde (108 IBU) and Brewdog Jack Hammer (220 IBU).
There are even beers that claim to have an IBU content of 1000…
Alcohol percentage: Alc 5%
The alcohol percentage is a figure that we are all very familiar with. Most beers have an alcohol percentage of between 5% and 10%. On the labels, the percentage is often referred to as alc. 5% vol. We also talk of percentage by volume. This means, half a litre of beer with 5% alcohol in volume contains 25 millilitres of alcohol. The alcohol percentage can also be referred to as a percentage of the weight. Because alcohol is lighter than water, the percentage by weight is lower than the percentage by volume.
Beer EBC: Colour
The colour of beer is measured in EBCs. EBC stands for European Brewery Convention. One EBC corresponds to 1 ml of iodine in 100 ml of water. There are also other methods used to indicate the colour of beer. For example, a similar scale is used in the United States, the so-called SRM scale.
- 6 - 9 EBC: Pale to light blonde, for example Kompaan Kameraad (7 EBC)
- 9 - 12 EBC: Blonde - yellow
- 12 - 20 EBC: Gold
- 20 - 30 EBC: Amber, for example De Koninck APA, (30 EBC)
- 30 - 45 EBC: Copper
- 45 - 75 EBC: Dark copper / brown
- 75 - 120 EBC: Very dark brown, transparent
- > 120 EBC: Black, not transparent, such as De Molen Hel & Verdoemenis (297 EBC)
Gravity is another term widely used by brewers. This value indicates the amount of solid ingredients before fermentation. The vast majority of these solids are sugars, which are converted into carbonic acid and alcohol during fermentation. The gravity is a fairly accurate indication of how much alcohol the beer will ultimately contain.
Gravity is measured using the Plato scale. This value is used in the Netherlands to calculate the excise duty that brewers should pay. You may have noticed that on the labels of a Dutch beer bottle you always see a category designation (Cat.). For example, a pilsner is in Category 1. This means that it has a gravity of between 11 and 15.5 Plato. Heavy beers are classified in Category S and have more than 15.5 Plato.
Based on these figures you now have a good idea of what beer you are dealing with. Fortunately, that image is not complete - watching, smelling and, above all, tasting is still the best way to truly get to know a beer.