Bitterness
Term from the Brauwerkstatt brewing glossary, category “Tasting and sensory”.
Explanation
The bitter taste in beer, mainly from the alpha acids of hops, which are isomerised during the boil. It is measured in IBU. How bitter a beer tastes also depends on the malt: plenty of sweetness softens the bitterness, plenty of sulphate in the water accentuates it.
Test your knowledge
What does the abbreviation IBU stand for?
- Alcohol content
- Beer colour
- Bitterness units
Show answer
Correct: Bitterness units. IBU means “International Bitterness Units”. 1 IBU equals about 1 mg of iso-alpha acids from hops per litre of beer.
What is dry hopping?
- Adding hops at the start of the boil for bitterness
- Adding hops to the fermenting or young beer for more aroma
- Closing the fermenter with a stopper
Show answer
Correct: Adding hops to the fermenting or young beer for more aroma. With dry hopping the hops add almost only aroma and hardly any bitterness, because they are not boiled.
Why is the wort boiled?
- So that the yeast can grow
- To create alcohol
- To sterilise it, to get bitterness from the hops and to drive off unwanted compounds
Show answer
Correct: To sterilise it, to get bitterness from the hops and to drive off unwanted compounds. Boiling sterilises the wort, turns alpha acids into bitter iso-alpha acids and drives off DMS.
Frequently asked questions
My hops have a different alpha acid than the recipe. What now?
Bitterness rises directly with alpha acid. Enter your value in the final-beer calculator and adjust the amount until the target IBU matches again.