Wort Boiling

Question 1

Reasons for boiling

Answer 1

Sterilisation, stabilisation, removal of unwanted flavours, addition of bitterness, aroma development, colour development, trub formation, pH drop.

Question 2

Millard reaction

Answer 2

During the boil, the heat causes a reaction between sugars and amino acids in the wort(derived from the malt) which results in sweet, bready and charamel aromas

Question 3

Main factors effecting wort efficiency

Answer 3

Time-
Evaporation-
Energy input
Hop addition timing
pH

Question 4

Evaporation equation

Answer 4

Percentage evaporation = end of boil gravity - start of boil gravity
——————————————
End of boil gravity
x100

Question 5

Parameters that we measure and control during wort boiling.

Answer 5

1. Time
2. Evaporation rate
3. Energy input
4. Hop addition timing
5. pH

Question 6

Isomerisation

Answer 6

Is a chemical process whereby the molecular structure of the a-acid is rearranged. This alters it’s chemical properties and reactions. The wort boiling process is thus necessary, as it changes a-acids to iso-a-acids (if your not using pre-isomerise hop products)

Question 7

IBU

Answer 7

1 international bitterness unit is one milligram of iso-a-acids in 1 litre of wort or beer

Question 8

Internal coils kettle

Answer 8

Difficult to clean, fouling, corrodes easily

Question 9

Calandrias

Answer 9

She’ll & tube heat exchanger
- large surface area
-turbulent flow
- internal or external heating

Question 10

External wort boiler

Answer 10

Wort I’d pumped through the calandria and heated as it heads to boiling.
- external loop is easier to clean
- external calamdria means kettle can also be used as whirlpool.