Tannins (astringency)
Term from the Brauwerkstatt brewing glossary, category “Faults and hygiene”.
Explanation
Tannins from husks and hops make your mouth feel dry and rough, rather like cold black tea. They dissolve especially when the sparge water is hotter than 78 °C (172 °F), the pH rises above 6 during lautering or you squeeze the grain.
Test your knowledge
What is chill haze?
- A haze that forms in cold beer and disappears when it warms up
- An infection
- The yeast sediment in the bottle
Show answer
Correct: A haze that forms in cold beer and disappears when it warms up. It forms from proteins and tannins. It is harmless and only affects the appearance.
How can you tell the hot break has happened?
- A firm white layer of yeast forms on top of the wort
- Shortly after coming to the boil the wort looks like egg drop soup
- The wort suddenly turns completely clear and dark
Show answer
Correct: Shortly after coming to the boil the wort looks like egg drop soup. In the hot break, protein and tannins flocculate. The wort then looks flaky, like egg drop soup.
Why do you stop lautering when the last runnings get very thin?
- Because it would push the alcohol above 10 %
- Otherwise the wort curdles in the kettle
- They add hardly any sugar but plenty of harsh tannins
Show answer
Correct: They add hardly any sugar but plenty of harsh tannins. Below about 1 to 2 °P the last runnings add almost no sugar but extract tannins from the husks.