SAQ Suggested Response - Q2

Question 1

What is the optimal pH range for mash?

Answer 1

5.2-5.4

This range balances enzyme activity and brewing benefits.

Question 2

List the benefits of maintaining a mash pH of 5.2-5.4.

Answer 2

• Enhanced protein coagulation
• Improved foam stability
• Reduction in wort viscosity
• Reduction in the extraction of polyphenols
• Lower colour forming potential
• Increased flavour stability

These benefits contribute to the overall quality and stability of the beer.

Question 3

Which enzymes have optimal activity at a mash pH of 5.2-5.4?

Answer 3

• Carboxypeptidases
• Aminopeptidases
• Limit dextrinase
• β-amylase
• ɑ-amylase

These enzymes are crucial for breaking down proteins and starches efficiently.

Question 4

What is the first step to ensure mash pH is within the optimal range?

Answer 4

Measure the mash pH

Measurement should be taken at the mash temperature as it affects pH.

Question 5

What factors in water can affect mash pH?

Answer 5

• Levels of calcium
• Levels of magnesium
• Levels of bicarbonate

These components influence both the pH and buffering capacity of the mash.

Question 6

What can be done if the mash pH is too high due to bicarbonate levels in water?

Answer 6

• Remove bicarbonate using lime treatment
• Boiling
• Reverse osmosis
• Ion exchange
• Addition of acids

These methods help to adjust water composition before mashing.

Question 7

Why is calcium preferred over magnesium for reducing mash pH?

Answer 7

Calcium produces a greater pH reduction and stabilizes ɑ-amylase at higher temperatures

This is important for maintaining enzyme activity during mashing.

Question 8

How can malts affect mash pH?

Answer 8

Darker malts lower the pH due to higher melanoidins

Using darker malts may not be viable if flavour and colour are important.

Question 9

What are acid malts used for in mashing?

Answer 9

To reduce mash pH

Acid malts carry lactic acid on their surface.

Question 10

What is a practical method to manage mash pH after mashing in?

Answer 10

Add acid to the mash

Phosphoric and lactic acids are commonly used for this purpose.

Question 11

What is sour wort and how is it used?

Answer 11

Diluted first worts acidified by lactic acid bacteria

It can impart a softer flavour to the beer.

Question 12

What should be controlled to manage mash pH effectively?

Answer 12

• Ionic composition of the water
• Grist composition
• Mash temperature
• Water to grist ratio

These factors should align with the requirements of the beer being brewed.

Question 13

Fill in the blank: The most common acids used to adjust mash pH are _______ and _______.

Answer 13

[phosphoric acid], [lactic acid]