Boiling and hopping the wort

What you need

• A kettle with enough headroom, as the wort foams when it comes to the boil
• Hops weighed out per addition
• A timer
• Optional: Irish moss or Protafloc for a clearer beer

Step by step

1. Step 1Heat up and skim

   Bring the wort to the boil. Just before it boils, protein foam forms. Stay close, turn the heat down if needed and skim off the foam so nothing boils over.

2. Step 2Keep a rolling boil

   The wort should visibly roll, not just simmer. Leave the lid off or half on so DMS can evaporate. Otherwise the beer tastes of cooked vegetables.

3. Step 3Add the bittering hops

   The first hop addition usually goes in at the start of the boil and boils for 60 to 90 minutes. It mainly gives bitterness and hardly any aroma.

4. Step 4Add the aroma hops

   Additions 10 to 20 minutes before the end of the boil give flavour, additions at flame-out mainly aroma. Set the timer for each addition.

5. Step 5Add a fining agent

   Add Irish moss or Protafloc 10 to 15 minutes before the end of the boil if you want a clear beer.

6. Step 6Whirlpool

   After the boil, stir the wort vigorously in a circle and let it rest for 10 to 20 minutes. Hops and trub collect in the middle. Hops added now at 70 to 80 °C (176 °F) give lots of aroma and only a little bitterness.

7. Step 7Check volume and gravity

   At the end, measure the volume and original gravity. You need these values for the final beer calculator and to fine-tune your system for the next batch.

Tips and common mistakes

• Bitterness depends on the amount, alpha acids and boil time. The final beer calculator works out the IBU with the Tinseth formula, including whirlpool hops.
• Pellets give a little more bitterness than whole hops.
• Note how many litres boil off per hour. With this value the water volume calculator will be spot on next time.