Section 1: Beer Types; Their Raw Materials; Sweet Wort Production.

Question 1

What is beer in terms of typical ingredients and methods of production?

Answer 1

Beer is an alcoholic beverage produced by the fermentation of sugars derived from malted barley and flavored with hops.

Question 2

What are the general characteristics of lagers?

Answer 2

Lager: German for "store" 
Use of relatively undermodified and lightly kilned malt.
Relatively low bitterness
Use of bottom fermenting yeast
Undertakes Cold maturation

Question 3

What are the general characteristics of ales?

Answer 3

Ales:

• Use well modified and biscuity flavoured malt, sometimes highly coloured, leading to malty and toffee characteristics and rich Amber or dark colours.
• Sometimes very bitter
• use of top fermenting yeast
• fermentations that are warmer and quicker than lagers. Leading to higher levels of fruity flavours

Question 4

What are the general characteristics of stouts?

Answer 4

Stouts:

• use top fermenting yeast
• warm, fast fermentations
• possible burnt or bitter aftertaste, due to the malt or rapist barley.
• traditionally high alcohol content, recent stouts usually have alcohol levels comparable to ales.

Question 5

What are the special attributes of barley for malting?

Answer 5

• plant can be grown in many parts of the world
• uniform size makes it easy to handle on an industrial scale
• 60 to 65% by dry weight of starch, together with protein, enzymes, vitamins and minerals the grain provides a complete package for yeast nutrition. Malt also contains sufficient lipids for yeast nutrition under anaerobic conditions.
• the husk is relatively tough, and can form a filter bed in the brewhouse.
• contains acceptably low levels of oils and lipids which are present to excess in some other seeds. Excessive levels of oils have deleterious effects on beer processing quality.

Question 6

What is the role of barley as the principal source of starch in brewing?

Answer 6

Starch is present in the endosperm of the barley corn as granules. The starch granules are embedded in a protein matrix. The protein matrix is surrounded by cell walls containing beta-Glucan, which protects the starch from amylase enzymes that are produced during germination. In the malting process the cell walls and the protein will be dissolved by other enzymes produced naturally as the seed grows.

Question 7

What are the significant changes that occur when the barley grain is malted?

Answer 7

• starch is made readily available for the mashing process to be converted into a range of fermentable and Unfermentable sugars.
• provide a source of amino acids and proteins for the yeast to be able to grow healthily during fermentation.
• develop desirable colours and flavours which are not present in barley itself.
• produce a final product that is stable and capable of storage and transport to the brewery.
• produce a food product which is wholesome and meets food quality criteria.

Question 8

What are the principal constituents of malt?

Answer 8

Constituents as % content of malt:

Starch 58%
Sucrose 3-5%
Soluble gum 2-4%
Hemicellulose 6-8%
Protein 8-11%
Amino acids/peptides 1-2%

Question 9

In regards to malt What is degree of modification?

Answer 9

Degree of modification is the extent to which the barley endosperm cell walls, proteins and to a lesser extent the starch granules themselves are broken down.

Question 10

In regards to malt what is extract content?

Answer 10

Extract content is the level of extractable carbohydrate within the malt kernel

Question 11

In regards to malt What is moisture content?

Answer 11

The % amount of water left within the malt kernel.
High grain moisture and temperature would normally denature the enzymes developed during germination, however the malt kilning
Process is manipulated to that the malt is dried at a relative low temperature ~50 C using highly air flow.
Kilning is done at 50 C until moisture content is 10% then the temp is raised to 90 C , the final moisture content should be 3-5%.

Question 12

In regards to malt What is colour?

Answer 12

Colour in malt is produced when sugars and soluble protein react together at high temperatures. This is called the Maillard reaction.
Increase in colour occurs depending on the degree of kilning and the levels of sugar and soluble protein present.

Question 13

What are the selection criteria for malt for ales?

Answer 13

Ale malt is well modified

Malt grain is softer and friable compared to lager malt.

Question 14

What are the selection criteria of malt for lagers?

Answer 14

Lager malts are less modified (less break down of cell walls and proteins)
Malt grain is Comparatively hard and not very friable.

Question 15

What mash conversion method is used for lagers?

Answer 15

Due to lack of protein breakdown for lager malt, beers brewed using lager malt may require additional processing to enable further protein and beta-Glucan breakdown during mashing in the brewhouse.
This may require the use of doctrine mashing, rising temperature infusion mashing and/or additions of enzymes produced by bacteria or fungi to the mash, to enable appropriate breakdown of starch granules to sugars.

Question 16

What mash conversion method(s) are suitable for beers using ale Malts?

Answer 16

Beers brewed using ale Malts may be brewed in simple mash tuna with no additional mixing or heating.

Question 17

What mash conversion system(s) can be used for coloured malts?

Answer 17

Any mash conversion system can be used for coloured malts.

Question 18

What pre-acceptance checks need to be made at malt intake?

Answer 18

-verification of type and batch against delivery plan.
-visual assessment:
#pests-beetles, weevils, moths etc.
#grain Size and uniformity (backed up with screening test)
#broken grain and missing husk
#foreign objects; other seeds, metal, stones, string etc.
#different colour grains (AKA Magpie effect)
#mould
-cut or bite; a longitudinal or horizontal cut will reveal steely (hard, unconverted/undermodified) parts of the grain. for Crystal malt reveals any non-glassy (undermodified) areas.
-flavour malt grains are sucked not chewed: pale malts should have a slightly sweet biscuity flavour (colour^=flavour^) chocolate darker malts should have a predominate acrid flavour.

Question 19

Why are adjuncts used?

Answer 19

• to change the character of the beer by altering its colour or flavour.
• to improve the quality of the beer eg head stability, increase or decrease wort fermentability, or reduce potential for haze formation.
• Increase capacity of the brewhouse by addition of liquid adjuncts to the wort boiling vessel
• reduce production costs
• increase brewhouse capacity
• improve brewhouse yield: eg replacing some malt with sugar syrup.

Question 20

What are the four main types of adjuncts

Answer 20

• Malted cereals: used in grist
• Processed cereals: used in grist
• Unprocessed cereals: need additional processing in brewhouse.
• Sugars or syrups: added to the copper/kettle or later in the process

Question 21

What is coloured malt?

Answer 21

Coloured malts are used to increase beer colour and/or to modify flavour.
They produce a more stable beer.
During the extra killing the proteolytic and amylolytic enzymes will have been destroyed.

Question 22

Crystal malt as a adjunct

Answer 22

Crystal malt is produced by a different killing procedure.
In-kilned germinated (green) malt or kilned pale malt rewetted to achieve high moisture content, is heated on the kiln and is “stewed” before mbeing dried and kilned again.
High colour and distinctive toffee flavours are produced as a result.
Crystal malt is used in ale brewing to provide a rich red colour and distinctive flavour. Colour is 140-170 degEBC

Question 23

Catapults and Munich malt as adjuncts

Answer 23

Similar to crystal malt but with lower colour and more delicate flavour, using undermodified malt followed by less kilning.

Used to add colour and flavour to lagers.
Munich -> 17-30 degEBC
Carapils -> 15-30 degEBC

Question 24

Amber Malt as an adjunct

Answer 24

Produced by roasting almost fully dried malt (the level prior to finial kilning) in a drum to give slightly higher colour and biscuity flavour. Colour typically 90-190 degEBC
Can be used instead of crystal. Giving a more dyer finish to the beer than crystal.

Question 25

Brown Malt as an adjunct

Answer 25

Produced from standard malt that has had extra kilning, usually by wood burning fires.
Used to ass lots of colour and oaky character to beers. Colour 140-160 degEBC
Often used in porters and stouts.

Question 26

Black and chocolate malts as adjuncts

Answer 26

Produced by roasting finished malt in a drum. Both malts have a high colour and a dry bitter flavour. Used in stouts to give a very dark and Hooghly flavoured beer. Very small quantities may be used to add colour to bitter type beers, without adding the flavour that crystal or Amber malt would give. Colour 1200-1400 degEBC

Question 27

Roasted barley as an adjunct

Answer 27

Used to contribute colour and distinctive burned coffee flavour to stouts.
900-1500 degEBC

Question 28

Wheat as an adjunct

Answer 28

Malted wheat:
-used as main carbohydrate source in Munich weissbier.

Torrified Wheat:

• produced by heating the moistened but unmalted grain to rupture the internal structure and release the starch for access during mashing.
• used up to 10% to improve head stability and save cost as it is a lot cheaper than malt.

Wheat Flour:

• produced by milling wheat
• used up to 10% to improve the beer’s head stability, reduce protein levels in grist, and save costs

Question 29

Maize as an adjunct

Answer 29

• Cheap source of carbohydrate
• starch is readily available but must be ‘gelatinised’ at high temperature before it can be converted to fermentable sugar,
• used up to 20% in lagers to reduce malty flavour and produce a clean delicately flavoured beer

Maize Grits:
Produced by milling maize and removing the germ (containing the protein and oil)maize grits must be cooked in the brewhouse to gelatinise the starch. Is cheaper than malt :. Can reduce costs

Maize flakes:
produced by Processing Frits through hot rollers :. Gelatinising the starch, making it accessible to the malt enzymes

Question 30

Rice as an adjunct

Answer 30

Used up to 30% of grist. Used the same way as maize (grits and flakes)

Question 31

Oats as an adjunct

Answer 31

Can be added in flake form to the mash tun/mash conversion vessel where the malt enzymes can work on the starch in the oats. Give a smooth silky mouthfeel and creaminess to stouts and porters

Question 32

Rye as an Adjunct

Answer 32

Rye can be added as malted rye or unmalted to the mash conversion vessel/mash tun. Or as whole grains to the a cereal cooker at 10-20% of the total grist. Rye increases palate fullness and a crisp slightly spicy flavour.