Malt Quality

Question 1

What does CoA stand for?

Answer 1

Certificate of Analysis

Question 2

What are the top 3 things that are the most important in influencing extract recovery in the brewhouse?

Answer 2

Variety
Total nitrogen
Kernel size

Question 3

The higher the nitrogen, the lower the amount of starch.

True or False?

Answer 3

True

Question 4

How do you find the percentage of protein from nitrogen?

Answer 4

Multiply the nitrogen by 6.25

Question 5

What does the Maillard reaction involve?(4)

Answer 5

Time
Temperature
Amino groups
Reducing sugars

Question 6

What does SRM and EBC stand for and what does it represent?

Answer 6

They both are a measure of colour.
SRM - Standard Reference Measure
EBC - European Brewing Convention

EBC = 1.97xSRM

Question 7

What are 4 methods of modification?

Answer 7

Friability
Fluorometric
Coarse Fine Differnce
Soluble Nitrogen Ration (Kolback Index)

Question 8

In the CoA what can the kernel size be referred too?

Answer 8

Assortment or Plumpness homogeneity

It is measured using a sieve with 2.2 mm holes

Question 9

If malt has a high moisture content how does that effect its life?

Answer 9

The malt can also lose its aroma during storage and may be more prone to fungal attack - Known as slack malt.
This isn’t defined by moisture, its defined by the inability to mill it properly, or to store it safely.

Question 10

What does the Kolbach index tell us?

Answer 10

How well the protein matrix has been broken down.

Its a very good indication of modification.

Question 11

How do you determine the extent of protein modification that has occurred from the Kolbach index?

Answer 11

It is easily calculated by measuring total nitrogen (TN) and total soluble nitrogen (TSN)
Typical specification are 38-45%

Question 12

What does the fine extract and coarse extract show us?

Answer 12

The different extract values between finely and coarsely milled malt and also give you an indication of how well the cell walls have been degraded.
Good results will be between 0-0.5% any thing over 1.5% indicates low modification

Question 13

What is Friability?

Answer 13

The percentage of malt that passes through the sieve (drum sieve and gently crushed) The number should be high if the malt is well-modified; a normal range is 85-95%.

Question 14

What is Homogeneity?

Answer 14

Measure of uniformity of modification

Question 15

A lack of grain modification leads to what?

Answer 15

High β-glucan levels

Question 16

What does the fluorometric test do?

Answer 16

Determines levels of β-glucan to see how modified the malt is.

Question 17

What is Free Amino Nitrogen?

Answer 17

An analysis that can indicate the amount of free amino groups available to yeast during fermentation.
A standard FAN value for most base malts is 180ppm and above.

Question 18

What is Diastatic power?

Answer 18

Measures the total enzymic activity available to break down the starch, α and β-amylases.

Question 19

Enzyme activity is often presented on malt analysis sheets as what?

Answer 19

Saccharification time

Typically 5-10 min, or 10-15 min. As you would expect, anything longer than 15 min suggests a problem.