unit 2 lesson 4 Flashcards
1
Q
What is an adjunct in brewing?
A
A supplementary raw material other than malted barley that provides a source of fermentable sugars
Adjuncts are often cheaper than malted barley and offer various benefits.
2
Q
What are the two classifications of adjuncts?
A
Mash adjuncts and kettle/post kettle adjuncts
Mash adjuncts contain starch and are added to the mashing vessel, while kettle/post kettle adjuncts contain fermentable sugars.
3
Q
What is the purpose of using adjuncts in brewing?
A
- Reduce raw material costs
- Extend brewhouse capacity
- Provide specific beer attributes (flavour, foam stability)
Adjuncts can enhance the quality and diversity of beers.
4
Q
What is the Reinheitsgebot?
A
A German purity law introduced in 1516 that allows only water, malted barley, and hops to produce beer
This law limits the use of adjuncts in Germany but not outside of it.
5
Q
What are basic cereals in the context of adjuncts?
A
Unmalted barley and wheat that can be milled as a small proportion of the malted barley grist
Using more than a small percentage can cause wort separation and beer filtration problems.
6
Q
True or False: Adjuncts can improve beer foam stability.
A
True
Wheat is a good source of high molecular weight proteins that contribute to foam stability.
7
Q
What is colloidal stability in beer?
A
How unlikely a filtered beer is to form a haze over time
A beer with high colloidal stability will not go hazy before the end of its shelf life.
8
Q
Fill in the blank: Adjuncts that contain starch are added to the _______.
A
mashing vessel
9
Q
What is a disadvantage of using adjuncts in brewing?
A
- Reduction in nitrogenous material
- Reduction in mash enzyme levels
- Reduction of beer colour
- Requirement for additional processing equipment
- Safety concerns
- Wort separation problems
Each of these factors can negatively impact the brewing process or the quality of the beer.
10
Q
What does free amino nitrogen (FAN) contribute to yeast?
A
It enables yeast to grow new cells and ferment wort effectively
Lack of FAN can cause slow fermentations and off-flavours.
11
Q
What are β-glucan and pentosans?
A
Long chain carbohydrate molecules that form gums when hydrated
They can cause filtration problems in the brewing process.
12
Q
What is the impact of using adjuncts on beer flavour?
A
Adjuncts can result in a lighter, cleaner flavour in beer compared to all-malt beers
Different adjuncts will have unique impacts on the attributes of the finished beer.
13
Q
What is the purpose of specifying the composition of adjuncts?
A
To understand how the composition affects the brewing process and the final product
Variations in composition can influence brewing efficiency and beer quality.
14
Q
What is the effect of using too many adjuncts on foam stability?
A
It can lead to insufficient proteins and polypeptides, causing poor foam stability
Yeast requires these compounds for effective fermentation and foam stability.
15
Q
What equipment might be required for processing certain adjuncts?
A
- Cereal cooker
- Specific handling and storage equipment for flours
- Equipment for sugar syrups
The cost of this equipment must be considered against the savings from using adjuncts.
16
Q
True or False: Adjuncts can create safety hazards in the brewery.
A
True
Flour and starch products can be highly combustible and pose explosion risks.
17
Q
What happens to the nitrogen concentration in wort when adjuncts are used?
A
It decreases, leading to potential issues with yeast performance
This can cause slow fermentations and off-flavours in the beer.
18
Q
What are β-glucans and pentosans?
A
Long chain carbohydrate molecules that form gums when hydrated
They can cause filtration problems in the brewing process.
19
Q
What issues do high molecular weight β-glucan molecules cause in the brewing process?
A
They can increase viscosity and lead to filtration difficulties
They also pose a risk of glucan haze formation in the beer.
20
Q
Which cereals are relatively high in pentosans?
A
Wheat, rye, and triticale
They cause similar filtration problems to β-glucans.
21
Q
Where are the bulk of proteins found in cereals?
A
In the endosperm
They are stored as building blocks of new plants.
22
Q
What percentage of wheat’s storage protein is made up of glutens?
A
80%
Compared to barley, which has 5-8%.
23
Q
What does the term ‘gluten’ mean?
A
Derived from the Latin word meaning ‘glue’
It is a composite of storage proteins in grains such as wheat, barley, and rye.
24
Q
What are the two main classifications of storage proteins?
A
Prolamins and glutelins
Prolamins include gliadins, hordein, secalins, and avenins.
25
What is the primary storage protein in barley?
Hordein
## Footnote
It makes up around 37% of the total barley protein fraction.
26
True or False: Wheat contains more protein than barley.
False
## Footnote
Wheat contains a greater proportion of higher-molecular-weight proteins.
27
What is the role of wheat glycoproteins in brewing?
Associated with good foam stability and haze formation
## Footnote
They contribute to the quality of the finished beer.
28
What are lipids?
Fats and oils found in all cereal grains
## Footnote
They serve as energy stores for the growth of new plants.
29
How can high lipid levels affect beer?
They can adversely affect beer flavor and foam stability
## Footnote
Lipids oxidize during production, generating off-flavors.
30
What effect do lipids have on foam stability?
They are foam negative
## Footnote
They interfere with hydrophobic foam stabilizers.
31
What is an adjunct in brewing?
A supplementary raw material other than malted barley
## Footnote
It provides a source of fermentable sugars.
32
What are unmalted adjuncts?
Solid cereals that require enzymes to convert their starch into sugars
## Footnote
They undergo processing to make starch available for conversion.
33
Fill in the blank: Solid adjuncts are processed in the _______.
Mash conversion vessel
## Footnote
This is where starch is converted into sugar.
34
What are the three steps of starch conversion?
* Gelatinisation
* Liquefaction
* Saccharification
## Footnote
These steps are essential for converting starch into fermentable sugars.
35
What conditions are necessary for gelatinisation of starch?
Moisture/water and thermal energy
## Footnote
Different starch granules have different gelatinisation temperatures.
36
What is the gelatinisation temperature range for barley?
75-80°C
## Footnote
This range indicates where barley can be effectively used in brewing.
37
What is the purpose of a cereal cooker?
To gelatinise starch before adding it to the mash conversion vessel
## Footnote
It allows for proper conversion into fermentable sugars.
38
What are grits?
Coarse milled fragments of starchy endosperm
## Footnote
Commonly produced from maize, sorghum, and rice.
39
What happens to the lipid, ash, and fiber content during grits preparation?
They are reduced by removing surface layers and embryo
## Footnote
This makes grits more suitable for brewing.
40
What is refined maize grits?
Purified starch with lower protein and lipid levels
## Footnote
They are smaller in size and easier to process.
41
What is the risk associated with the residual lipid content in stored grits?
It can oxidize and cause rancidity
## Footnote
This necessitates careful management of stocks.
42
What is flour in the context of brewing?
The smallest particle size of solid adjuncts
## Footnote
It can be produced on-site or off-site.
43
What problems can arise from using whole wheat kernels in the brewing process?
They can introduce lipids, large proteins, and β-glucans
## Footnote
This can lead to increased wort viscosity and filtration issues.
44
What is air classification?
A system that separates particles based on size, shape, and density
## Footnote
It is used to produce purer flour for brewing.
45
What are the hazards associated with handling flour?
Flour poses explosion risks, inhalation causes allergies and respiratory harm
## Footnote
Handling flour requires special equipment due to its hazardous nature.
46
What is required to handle flour safely in a brewery?
Specially designed hoppers and dedicated pneumatic and vibrating conveying systems
## Footnote
These systems help in managing the flow of flour effectively.
47
What are pre-gelatinised cereals?
Cereals that have been partially cooked to gelatinise starch molecules
## Footnote
They can be used as a solid adjunct in brewing.
48
How are micronised cereals processed?
Heated using infra-red radiation at 260°C for a short duration
## Footnote
This process causes the grains to swell and pop.
49
What is the torrefaction process in cereal adjuncts?
Involves adjusting moisture levels and passing air at 410°C to expand grains
## Footnote
This process reduces grain density and is faster than micronisation.
50
How are flaked products produced?
By adjusting moisture, cooking with steam, rolling through heated rollers, and drying
## Footnote
Modern methods use micronisation or torrefaction before flaking.
51
What is a key disadvantage of using flour as an adjunct?
Higher potential for brewhouse processing issues like slow runoff
## Footnote
Excessive use of flour can complicate the brewing process.
52
What are liquid adjuncts?
Products where the manufacturer has converted raw materials into sugars for fermentation
## Footnote
They can be added during boiling or later in the brewing process.
53
What are the advantages of using liquid adjuncts in brewing?
* Increased brewhouse output without larger equipment
* Better control of wort sugar spectrum
* Precise control of original gravity
* Influence on palate fullness
* Impart novel flavors
## Footnote
These benefits contribute to more efficient brewing processes.
54
What is necessary for the storage of liquid adjuncts?
Storage tanks need to be heated, insulated, and ventilated to prevent microbial spoilage
## Footnote
Maintaining temperature above 70% sugar by weight is critical.
55
What processes are used to manufacture starch-derived liquid adjuncts?
* Acid hydrolysis
* Acid/enzyme starch hydrolysis
* Enzyme starch hydrolysis
## Footnote
These processes convert starch into fermentable sugars.
56
What is the composition of dextrose and maltose syrups?
Rich in glucose and maltose but also contain other sugars and dextrins
## Footnote
Specifications vary by supplier.
57
How does yeast react to high glucose concentrations in worts?
Yeast ferments glucose first, potentially leading to stuck fermentations
## Footnote
This issue does not occur with worts high in maltose and sucrose.
58
What is the primary sugar in maltose syrup?
Maltose, which is a disaccharide made of two glucose units
## Footnote
Produced using pullulanase and β-amylase.
59
How is sucrose syrup produced?
Extracting juice from sugar cane or beet, clarifying, evaporating, and crystallising
## Footnote
The process involves multiple steps to refine the sugar.
60
What enzyme does yeast use to break down sucrose?
Invertase
## Footnote
It converts sucrose into glucose and fructose.
61
What are some examples of sucrose-based liquid adjuncts?
* Molasses
* Invert sugar
* Belgian candi sugar
## Footnote
These adjuncts provide unique flavors and characteristics to the beer.
62
What is the role of invert sugar in brewing?
Provides fermentable sugars by hydrolysing sucrose into glucose and fructose
## Footnote
Invert sugar is completely fermentable.
63
What is the significance of molasses in brewing?
Contains higher concentrations of non-sugar components and is 75% fermentable
## Footnote
Care must be taken to avoid off-flavors.
64
What is the relationship between the proportion of molasses and color in brewing?
The greater the proportion of molasses, the higher the colour.
65
What is Belgian candi sugar?
Solid crystals of sucrose coated with a coloured sugar product produced by heating.
66
What is the process for producing candi sugar?
An 80% Brix sucrose solution is heated to 50°C until the appropriate colour forms, which can take up to five days.
67
What is candi concentrate?
The coloured syrup left behind after sucrose crystals are removed.
68
What are the ranges of candi sugar by EBC?
From light candi sugar at 225 EBC to dark candy sugar at 1900 EBC.
69
What happens to sucrose during the heating process of candi sugar production?
It undergoes hydrolysis (inversion) to produce fructose and glucose.
70
What are the main components of honey?
95% fermentable sugars, including 38% fructose, 30% glucose, 8% various disaccharides, and 3% dextrins.
71
Why should honey be added after wort cooling?
To minimize the loss of honey aroma due to evaporation.
72
What disaccharide is present in honey that ale yeast cannot ferment?
Melibiose.
73
What is the purpose of invertase in honey?
To hydrolyse sucrose into simpler sugars.
74
What are some other syrups that can add flavor attributes to beer?
* Agave nectar * Maple syrup.
75
What does Dextrose Equivalent (DE) measure?
The extent to which starch molecules have been converted to sugar.
76
What is the DE of pure starch?
Zero.
77
What is the DE of dextrose/glucose?
100%.
78
What is the standard method for measuring DE in syrups?
Lane-Eynon titration.
79
What does Brix measure?
The w/w % of sucrose in a solution.
80
How is Brix expressed?
As % or °Brix.
81
What does a refractometer measure?
The degree of refraction of light through a liquid, indicating the amount of dissolved substance.
82
What are typical parameters measured for high maltose syrup?
* Appearance * DE * Maltose % * Brix° at 25°C * SO2 PPM * Sulphated Ash * pH * Arsenic * Heavy Metals (Lead) * Total Plate Count * Yeasts & Moulds * E. coli * Salmonella.
83
What is the minimum appearance specification for high maltose syrup?
Colourless to high yellow coloured syrup.
84
What is the maximum pH for a 1:1 aqueous solution of high maltose syrup?
6.
85
What are the two main types of brewing adjuncts?
* Solid adjuncts * Liquid adjuncts.
86
What should brewers analyze in liquid adjuncts?
How and how much of the product to use.
87
What are the learning outcomes of the lesson on brewing adjuncts?
* Describe the use of adjuncts * Identify specifications and analysis methods * Critically evaluate solid adjuncts * Critically evaluate liquid adjuncts.
88
What is β-glucan?
A polysaccharide found in the cell walls of cereals like barley and oats
## Footnote
High molecular weight β-glucans can increase wort viscosity and cause filtration problems.
89
What does Brix measure?
The sugar content in a solution, expressed as a percentage
## Footnote
One degree Brix is equivalent to 1 gram of sucrose in 100 grams of solution.
90
What is the purpose of a Cereal Cooker?
To gelatinize starch in cereals with high gelatinization temperatures before adding them to the mash
## Footnote
This process involves heating the cereal with water to break down the starch.
91
What is Dextrose Equivalent (DE)?
A measure of the extent to which starch has been converted to sugar, expressed as a percentage
## Footnote
DE indicates the proportion of reducing sugars in a syrup compared to pure dextrose.
92
What is Enzyme Hydrolysis?
The process of breaking down starch into simpler sugars using enzymes
## Footnote
Common enzymes used in brewing include α-amylase, β-amylase, and amyloglucosidase.
93
Fill in the blank: One degree Brix is equivalent to _______.
1 gram of sucrose in 100 grams of solution.
94
True or False: β-glucans can decrease wort viscosity.
False
## Footnote
High molecular weight β-glucans can increase wort viscosity.
95
Fill in the blank: The Cereal Cooker is used to gelatinize starch in cereals like _______.
maize, rice, sorghum.
96
List three common enzymes used in brewing.
* α-amylase
* β-amylase
* amyloglucosidase
97
What does a higher Dextrose Equivalent (DE) indicate?
A greater proportion of reducing sugars in a syrup.
98
What is fermentability?
The proportion of sugars in wort that can be fermented by yeast
## Footnote
Higher fermentability means more sugars are converted to alcohol and carbon dioxide during fermentation.
99
What are flakes in brewing?
Cereal grains that have been steamed and rolled to gelatinize the starch
## Footnote
Flaked adjuncts, such as flaked maize or barley, can be added directly to the mash.
100
Define gelatinization.
The process of heating starch granules in the presence of water to unwind and expose glucose chains
## Footnote
Gelatinization is necessary for starch to be converted into fermentable sugars.
101
What are grits?
Coarse milled fragments of starchy endosperm from cereals like maize, rice, and sorghum
## Footnote
Grits require gelatinization before they can be added to the mash.
102
What is invert sugar?
A mixture of glucose and fructose produced by hydrolyzing sucrose
## Footnote
Invert sugar is completely fermentable and can be used to increase wort gravity and influence beer flavor.
103
How do lipids affect beer?
High lipid content can negatively affect beer flavor and foam stability
## Footnote
Lipids promote oxidation and reduce foam retention.
104
What is maltose syrup?
A commercial syrup rich in maltose, produced by enzymatic hydrolysis of starch
## Footnote
Maltose syrups typically contain a mix of maltose, glucose, and other sugars.
105
What are micronised cereals?
Cereals heated using infra-red radiation to gelatinize the starch
## Footnote
Micronised cereals are easier to handle and can be milled with malted barley.
106
What is pentose?
A type of polysaccharide found in cereals like wheat, rye, and triticale
## Footnote
Pentosans can increase wort viscosity and cause filtration problems similar to β-glucans.
107
Define pre-gelatinised cereals.
Cereals that have been heat-treated to gelatinize the starch before being added to the mash
## Footnote
Examples include torrefied and micronised cereals.
108
What is saccharification?
The enzymatic process of converting liquefied starch into fermentable sugars
## Footnote
This step follows gelatinization and liquefaction in the brewing process.
109
What is sucrose?
Common table sugar, a disaccharide composed of glucose and fructose
## Footnote
Sucrose is 100% fermentable and can be used to increase wort gravity and as a priming sugar for bottle conditioning.
110
What are torrefied cereals?
Cereals heated with hot air to gelatinize the starch and reduce density
## Footnote
Torrefied cereals are easier to handle and can be milled with malted barley.
111
What is wort?
The liquid extracted from the mashing process that contains fermentable sugars for fermentation
## Footnote
Wort composition is influenced by the types of adjuncts and malts used.
112
What is an adjunct in brewing?
Any supplementary raw material other than malted barley that provides fermentable sugars.
113
What are the two main categories of adjuncts?
* Mash adjuncts
* Kettle/post-kettle adjuncts
114
What are some main types of adjuncts?
* Basic cereals (unmalted)
* Raw grits
* Flakes
* Torrefied/micronised cereals
* Flour/starch
* Syrups
115
What is a historical use of adjuncts in brewing?
To supplement or replace malt as an additional source of extract.
116
What are some benefits of using adjuncts?
* Reduce raw material costs
* Extend brewhouse capacity
* Impart specific attributes to beers
117
How do adjuncts affect wort fermentability?
They provide specific proportions of fermentable sugars that can increase the concentration of fermentable sugars in the wort.
118
True or False: Beers brewed with only malted barley tend to have lighter flavors.
False.
119
What influence do adjuncts have on beer flavor?
Adjuncts can result in beers with lighter, cleaner flavors.
120
How can adjuncts improve foam stability?
By providing foam-positive material, such as high molecular weight proteins from wheat.
121
What can happen if adjuncts reduce nitrogenous material in wort?
It can lead to slow fermentations and increased off-flavors in the beer.
122
What is the role of free amino nitrogen (FAN) in brewing?
Yeast requires FAN to grow and ferment wort effectively.
123
What can excessive use of adjuncts lead to in terms of enzyme levels?
Insufficient enzyme activity in the mash to convert all the starch.
124
What is a potential disadvantage of using adjuncts in brewing?
Reduction in nitrogenous material and mash enzyme levels.
125
Fill in the blank: Adjuncts contribute little or no _______ to beer.
color
126
What safety concerns are associated with handling adjuncts?
The risk of explosions, particularly with flours and starch products.
127
What are some challenges related to wort separation when using adjuncts?
* Lack of husks for filtration
* Increased wort viscosity
128
What is the significance of understanding the composition of adjuncts?
It is crucial for predicting their impact on the brewing process and the final product.
129
What are the main types of proteins found in cereals?
* Gluten in wheat
* Hordein in barley
130
What can high lipid levels in adjuncts negatively affect?
Beer flavor and foam stability.
131
What are malted adjuncts used for in brewing?
To impart specific characteristics to beer rather than for cost benefits.
132
What processing step is required for solid adjuncts?
Their starch must be converted into sugar through gelatinization, liquefaction, and saccharification.
133
What are liquid adjuncts?
Products where the manufacturer has converted raw material into sugar for fermentation.
134
What are the benefits of using liquid adjuncts?
* Increased brewhouse output
* Better control of the wort sugar spectrum
* Precise control of original gravity
135
What is a common issue with high glucose syrup in fermentation?
Yeast may struggle to adapt to fermenting other sugars, leading to stuck fermentations.
136
What enzymes are used to produce maltose syrup?
* Pullulanase
* β-amylase
137
What does the term 'pre-gelatinized cereals' refer to?
Cereals that are partially cooked to gelatinize starch.
138
True or False: Solid adjuncts are more hazardous to work with than liquid adjuncts.
True.
139
What is the primary use of starch-derived liquid adjuncts like dextrose and maltose syrups?
To adjust the carbohydrate profile of the syrup for brewing.
140
What is a common characteristic of very high maltose syrups?
They contain about 70% maltose.
141
What is maltose syrup rich in?
Disaccharide maltose
## Footnote
Maltose syrup is produced using pullulanase and β-amylase enzymes
142
What enzymes are used to produce maltose syrup?
* Pullulanase (limit dextrinase)
* β-amylase
## Footnote
Pullulanase debranches starch chains, allowing β-amylase to produce maltose
143
What percentage of maltose do high maltose syrups typically contain?
Around 50% maltose
## Footnote
Very high maltose syrups contain about 70% maltose
144
What is sucrose syrup commonly known as?
Table sugar
## Footnote
Sucrose syrup is produced from sugar cane or sugar beet
145
List the steps involved in the production of sucrose syrup.
* Extracting juice
* Adjusting pH
* Clarifying
* Evaporating to concentrate
* Further clarifying
* Crystallizing
* Centrifuging
## Footnote
These steps separate crystals from the mother liquid
146
What enzyme does yeast use to break down sucrose?
Invertase
## Footnote
Yeast lacks a transporter system for sucrose
147
What is the fermentability percentage of sucrose?
100% fermentable
## Footnote
Sucrose is often used as a priming sugar for bottle and cask-conditioned beers
148
What are some other liquid adjuncts mentioned?
* Molasses
* Invert sugar
* Belgian candi sugar
## Footnote
Each adjunct has unique properties and uses
149
What is molasses a by-product of?
Sugar manufacturing
## Footnote
It contains higher concentrations of non-sugar components
150
What is the fermentability of molasses?
75% fermentable
## Footnote
It contains iron, which can cause off-flavors
151
What does invert sugar produce when made by heating a sucrose solution?
* Fructose
* Glucose
## Footnote
Invert sugar is produced using acid or the enzyme invertase
152
What is Belgian candi sugar composed of?
Sucrose crystals coated with a colored sugar product
## Footnote
Different grades are available, from light to dark
153
What does honey contain that makes it unique in brewing?
95% fermentable sugars
## Footnote
Honey adds unique aromas depending on the type and source
154
What disaccharide does honey contain that ale yeast cannot ferment?
Melibiose
## Footnote
Lager yeast can ferment melibiose
155
What is measured in the quality analysis of liquid adjuncts?
* Dextrose equivalent (DE)
* Brix
* Color
* pH
* % extract
* Microbial content
## Footnote
These parameters ensure quality of liquid adjuncts
156
What does dextrose equivalent (DE) indicate?
Extent of starch conversion to sugar
## Footnote
Pure starch has a DE of zero; dextrose/glucose has a DE of 100%
157
What does Brix measure?
Sugar content in a solution
## Footnote
Expressed as a percentage and measured using a refractometer
158
What parameters are included in the analytical specification of high maltose syrup?
* Appearance
* DE
* Maltose percentage
* Brix
* SO2
* Sulphated ash
* pH
* Arsenic
* Heavy metals
* Total plate count
* Yeasts and molds
* E. coli
* Salmonella
## Footnote
These specifications help brewers ensure quality standards
