Mashing

Question 1

What shape is amylose molecule?

Answer 1

Straight (unbranched) and helical

Question 2

What are the bonds between glucose residues called?

Answer 2

Glycosidic (glycosides)

Question 3

Why are glucose residues called such way?

Answer 3

They are no longer complete molecules when bound in a polymer (lose H2O)

Question 4

What shape is an amylopectin molecule?

Answer 4

Branched

Question 5

What type of glucose residue bond exists in branches of amylopectin?

Answer 5

a-(1,6) glycosidic bond

Question 6

Why is glucose able to reduce other compounds (redox reactions)?

Answer 6

Due to its free aldehyde group, which is oxidized in the reaction and changed to a carboxyl group

Question 7

What are proteins made of?

Answer 7

Polymers made up of amino acid residues

Question 8

What types of bonds link amino acids in protein structure?

Answer 8

Peptide bonds (formed with the loss of H2O)

Question 9

What are the 2 ends of a peptide/protein molecule?

Answer 9

Amino end (NH2) and Carboxyl end (COOH)

Question 10

What are the most notable non-starch polysaccharides in a mash?

Answer 10

Pentosans and beta glucan

Question 11

What are types of lipids?

Answer 11

Triglycerides (fats/oils), waxes, phospholipids and sterols

Question 12

What’s the difference between a saturated and unsaturated fat?

Answer 12

Saturated fat–every carbon has max number go hydrogen atoms attached

Question 13

Detrimental qualities of lipids

Answer 13

Foam, Flavor stability, Gushing, inconsistent ester formation

Question 14

What unsaturated fatty acid is thought to have a major role in beer staling?

Answer 14

Linoleic acid: oxidises to form precursor to E-2-nonenal

Question 15

What mash temperatures can be used to minimize LOX activity

Answer 15

Above 65 C

Question 16

What are the 4 classes of polyphenol structures?

Answer 16

Simple phenol-based molecule
Flavanols
Proanthocyanidins
Complex flavanols

Question 17

How can polyphenols help prevent beer staling?

Answer 17

Scavenging oxygen as they oxidize easily
Complex with metal ions that catalyze staling

Question 18

How to mash enzymes increase the rate of a chemical reaction?

Answer 18

They reduce the energy required for the reaction to occur

Question 19

What is hydrolysis?

Answer 19

Breaking of a bond with addition of water (opposite of condensation reaction)

Question 20

What are the enzymes that target B-glucans?

Answer 20

Endo B(1,4) glucanase, Endo B(1,3) glucanase, Barley B-glucanase

Question 21

What are the enzymes that target proteins?

Answer 21

B-glucan solubilase, Endoproteases, Carboxypeptidases, Aminopeptidases

Question 22

What are the enzymes that target starch?

Answer 22

A-amylase, B-amylase, Limit dextrinase, A-glucosidase

Question 23

What sugars do B-amylase produce?

Answer 23

Maltose

Question 24

How does Limit dextrine help define fermentability?

Answer 24

Produces more non-reducing ends for action of B-amylase

Question 25

What are negative effects of too extensive protein degradation?

Answer 25

Reduce foam and body, Too much FAN can increase color and flavor, increased staling

Question 26

What types of enzymes are carboxypeptidase and aminopeptidase?

Answer 26

Exoproteases

Question 27

What does B-glucan solubilase hydrolyze?

Answer 27

Protein cross-links between strands of B-glucan molecules

Question 28

What does the hydrolysis of triglycerides yield?

Answer 28

Free fatty acids

Question 29

What is a common set of mash temperature stands to hit each substrate?

Answer 29

45 C: B-glucanase 52 C: Protease 63 C: B-amylase 72 C: A-amylase 76 C: Mash off

Question 30

What is the heat of mash hydration called?

Answer 30

Slaking heat

Question 31

Why does pH of a solution fall as temperature rises?

Answer 31

Molecular vibration (heat) causes weak acid molecules to dissociate, releasing H+ ions

Question 32

How do you calculate the volume of boiled mash required in decoction?

Answer 32

Volume of boiled mash = (required temp rise x total mash vol) / (95 C - temp of unboiled mash)

Question 33

What enzyme doe maltase mashing target?

Answer 33

A-glucosidase (to produce more glucose)

Question 34

What type of mash profile is common for NA or low alcohol beers?

Answer 34

Jump mashing

Question 35

What breakdown of carbohydrate percentages is common in standard mash wort?

Answer 35

67% maltose 20% maltotriose 13% glucose Small amounts of sucrose/fructose

Question 36

What percentage of TSN is typically amino acids?

Answer 36

10-15% (140-160 mg/L)

Question 37

What test is done for wort fermentability?

Answer 37

Wort Attenuation Limit

Question 38

What is caused by uneven hydration of grist at mashing?

Answer 38

Agglutination

Question 39

What are a few examples of inline pre-mashers?

Answer 39

Cone pre-masher, vortex pre-masher, steinecker

Question 40

What is the latest pre-masher evolved from Steeles premasher that reduced O2?

Answer 40

Meura Mechamasher

Question 41

How do shear forces affect B-glucans?

Answer 41

Increase viscosity by promoting cross-linking and gel forming

Question 42

What are three types of mash heating jackets?

Answer 42

Conventional, half pipe and Dimple jackets

Question 43

What is the most efficient method of heat transfer to mash?

Answer 43

Steam injection (Meura Aflosjet)