Mash Thickness

Question 1

What is the mash thickness set by?

Answer 1

The ratio of water to grist (L of water:kg of malt)

This ratio is also known as the water to grist ratio.

Question 2

What are the water to grist ratios for a thick mash?

Answer 2

2:1

This is the lower limit for a thick mash.

Question 3

What are the water to grist ratios for a thin mash?

Answer 3

5.4:1

This is the upper limit for a thin mash.

Question 4

What is the water to grist ratio range for a mash tun?

Answer 4

2.2:1-2.7:1

This is one of the common wort separation devices.

Question 5

What is the water to grist ratio range for a lauter tun with mash conversion vessel?

Answer 5

2.5:1-3:1

This is another common wort separation device.

Question 6

What is the water to grist ratio range for a lauter tun with decoction?

Answer 6

3:1-5.4:1

This type of device allows for greater flexibility in mash thickness.

Question 7

What is the water to grist ratio range for a mash filter?

Answer 7

2.7:1-3.2:1

This ratio is important for achieving desired wort characteristics.

Question 8

What effect do thicker mashes have on wort viscosity?

Answer 8

Produce more viscous worts

Thicker mashes are harder to pump and agitate.

Question 9

What phenomenon can slow amylase activity in thicker mashes?

Answer 9

Competitive inhibition

This occurs when molecules block the enzyme’s active site.

Question 10

What is the extract efficiency of very thick mashes?

Answer 10

Low extract efficiency

However, minor differences exist within the standard range.

Question 11

What type of sugars do thicker mashes produce at high mashing temperatures?

Answer 11

Higher proportion of fermentable sugars

This contrasts with thinner mashes at standard temperatures.

Question 12

At lower temperatures, what do thin mashes favor?

Answer 12

Proteolysis

This is the breakdown of proteins into smaller peptides.

Question 13

What is the effect of thick mashes on total soluble nitrogen (TSN) and FAN?

Answer 13

Higher levels of TSN and FAN

More high molecular weight nitrogenous substances remain in solution.

Question 14

What is the effect of thick mashes on foam stability in beer?

Answer 14

Poorer foam stability

This is due to a lower proportion of foam-enhancing polypeptides.

Question 15

What is the pH trend in thicker mashes?

Answer 15

Lower pH and more stable

Thicker mashes resist changes in pH more readily.

Question 16

Name two characteristics of thick mashes compared to thin mashes.

Answer 16

• Slow starch conversion
• Higher TSN/FAN
• Lower extract efficiency
• Lower and more stable pH
• Higher fermentability at high temperatures
• Poorer foam stability

This highlights the differences in performance and output between the two types of mashes.

Question 17

What is true about starch conversion in thin mashes?

Answer 17

Faster starch conversion

This is a key advantage of using thinner mashes.

Question 18

What is the foam stability comparison between thick and thin mashes?

Answer 18

Thick mashes have poorer foam stability; thin mashes have better foam stability

This affects the quality of the finished beer.