Mod 3 Raw Materials Flashcards

1
Q

All water used during the production process in the Scotch whisky industry is
derived from

A

Rain or snow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The basic requirements of
water supply are that it is

A

adequate and available

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

water sources

A
  1. springs
  2. burns/rivers
  3. lochs
  4. wells
  5. boreholes
  6. mains
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Water is used in several key phases of the
production process (3)

A
  1. steeping & mashing - ph microbiological purity
  2. cooling - volume temp
  3. dilution - ph,hardness, volume, temp, microbiological content.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

why is it good to know the mineral content and ph balance of water when steeping and mashing

A

steeping and mashing are
basically biochemical processes, they can be
affected by the mineral and ion content - and by
the pH - of the water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why know hardness level

A

The mashing water used can influence the
fermentation, depending upon the hardness levels
and ions present.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

soft water

A

heavier new make

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Harder water

A

cleaner/sweeter new make
spirit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Cool Water

A

cool water is required for the
condensers, therefore the quality parameters here
are simply volume and temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Dilution

A

For cask filling. Water must pure
in terms of lack of solids and microbiological
content. Quality parameters that can be measured
therefore are pH, hardness, volume used,
temperature and microbiological content.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Once sourced, that water is used at four
key parts of the production process

A

steeping, mashing, cooling & dilution.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Main raw material in the production of single malt

A

Barley

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Malting barley moves through 3 key stages in the pre production process

A
  1. growth & harvesting,
  2. variety development
  3. testing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Growth and harvesting

A
  1. malting barleygrown predominately on east side of uk
  2. lower rainfall than the west
    3 . preferable soil
  3. Harvesting takes place in the second half of July
    and August in Southern England and East Anglia
    and can start four to six weeks later in Scotland
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Variety development

A

Each barley variety has different characteristics
and morphological features

some features are
1. grain shape
2. rachilla in ventral crease
3. Nerve pigment and colouring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Shape of grain

A

Is it bold, thin, or flat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Rachilla

A

a structure in the ventral crease, can be short or long.

Can have hairs that can be short and wolly or long and straight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what maltsters like in malting barley

A

Cost effective
* Bold grain
* Appropriate nitrogen level
* Good germinative ability
* Varietal purity
* Reliable supply
* Suitable storage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Best malting barley

A

homogenous bulk, with bold and even grains.

Grains of the same size will hydrate and process at
the same rate, leading to more homogenous malt.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Homogeneous Malt

A

Homogeneous simply means of the
same kind or alike. In malting, the
term is often used when describing a
sample of barley at intake.
Numerous samples, for example,
are taken from across the load and
mixed thoroughly to ensure, overall,
the sample is homogenous. Physical
features such as rachilla hairs and
spicules are assessed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Agriculture and
Horticulture Development Board (AHDB).

A

Testing and breeding system in the UK

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

produces a recommended lists of barley varieties
and recommends those to use in the various
industries.

A

Agriculture and
Horticulture Development Board (AHDB).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Testing is done

A

prior to maltsters buying barley

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

5 test on barley

A
  1. Nitrogen
  2. Moisture
  3. Screenings
  4. Germination
  5. Varietal purity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Reference method for nitrogen

A

Dumas method

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Near Infrared (NIR) equipment

A

equipment that most analysis is carried out on

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

barleyis dried because

A

a) off the field it is too wet for storage (in England the
moisture level is usually between 14-16% whereas in Scotland it can be up to
20%),

b) infestation can occur (insects cannot breed in barley if it is less than
15°C and less than 12% moisture

c) dry barley can be stored safely for
longer (germination potential can be inhibited if stored at higher moistures
and temperatures).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Insects cannot breed in what temps

A

(insects cannot breed in barley if it is less than
15°C and less than 12% moisture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

recognized industry levels for barley temps and moisture during storage are

A

are less than 12% moisture
& 15°C.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

how is barley dried

A

tower drier method

The drying is controlled by the rate of barley
flowing through the drier and the temperature of
the air being used. The wetter the barley, the lower
the air on temperature is required to be, as wet
barley can be damaged by heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

how is barely stored

A

Silos

ventilation systems normally suck air rather
than blow air. Flat store or ‘big shed’ have a
higher capital cost and can result in waste. The
air is blown through the bulk via permanent or
temporary air ducts.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

barely is stored

A

in a silo or flat store

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

steeping

A

raising the moisture level to such an extent that
germination is initiated.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

barely is dried prior to storage because

A

because, once off the field, it is
usually too wet to store. Drying barley also helps to reduce what is called dormancy in the grain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Dormancy

A

is the natural tendency
to inhibit germination, and can vary
depending upon variety, growing
conditions and harvesting conditions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

self-emptying cylindroconical vessel

A

very water efficient compared to false bottom
flat steeps, used for steeping

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

level of hydration in grain dependent on

A

Water temperature
* Grain size
* Variety
* Viability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Water temperature

A

Higher water temperature
results in more rapid water
uptake and may be required if
the grain is less mature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Grain size

A

Larger grains require more
time under water to reach
the same moisture level as
smaller grains.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Viability

A

The maturity (or viability)
of grain also affects water
uptake, with the barley
taking in water more
quickly as it matures.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Variety

A

Different varieties may take
in water at different rates,
so steeping cycles would
be altered

Optic typically
takes longer to reach the
same moisture level than
Concerto.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Multiple Steeping

A

The multiple steeping cycle normally takes place
over a 48-hour cycle and consists of two or three
‘wet’ periods, with ‘air rests’ in between.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is multiple steeping

A

The multiple steeping cycle normally takes place
over a 48-hour cycle and consists of two or three
‘wet’ periods, with ‘air rests’ in between.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Target moisture at the end of steeping

A

the mid-40s but the actual figure is dependent
upon the type of malt being made.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

higher steep out or cast moisture

A

result
in increased respiration and therefore increased
malting loss. It will also result in increased enzyme
activity and soluble nitrogen content.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Cast moisture

A

is the moisture level in the
grain as it is moved from the steeping
stage to the germination stage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Cast moisture

A
  1. the more water, the
    more active the grain, until you get to the
    stage where it will drown.
  2. The more active the grain, the quicker
    the breakdown processes inside the
    grain;
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Hydrolysis

A

the technical term for the
breakdown of starch into sugars.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Germination physical changes

A

After water intake, the grain has
swelled and a small white chit (root cover) can be
seen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Chemical Changes

A

Enzymes, stimulated by
the release of hormones, are released into the
endosperm degrading the cell walls and protein
matrix, thereby making the starch supply available
for hydrolysis during the mashing process.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Germination

A

produces the enzymes required for
the hydrolysis process. And distillers want the
starch and the enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Structures in barley grain related to germination

A
  • Micropyle
  • Embryo
  • Endosperm
  • Husk
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Germination

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Embryo

A

the living part of the grain,
sometimes called the germ; it is the ‘baby’ plant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Micropyle

A

the structure at the embryo end
of the corn that allows water to flow into the grain
(Basically, it is a hole that allows for water to
enter.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Husk

A

the ‘skin’ that surrounds and protects
the barley.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Endosperm

A

the food reserve for the embryo.
It is a hard structure consisting of starch molecules
(long chains of sugar molecules) embedded within
a protein matrix all surrounded by cell walls.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Endosperm during germination

A

altered due
to the action of enzymes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

what does the embryo release at the start of germination

A

a
hormone called Gibberellic Acid, known as GA3.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

MOdification Front

A

This initiates the aleurone layer to release
the enzymes required to break down the cell
walls, protein matrix and starch granules.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Modification front breakdown occurs

A

from the embryo end to the
distal end of the grain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Malting Loss

A

Germination is complete once the endosperm has
been made friable. That is, it can be rubbed out;
meaning the cell walls and protein matrix have
been broken down.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

starch is also broken down and used
for root and shoot growth, this usage is

A

Malting Loss

64
Q

Controlled Germination

A

Keeps malting loss at a minimum

more malting loss that occurs, the less starch available for distillers to work with

65
Q

Enzyme release timing

A
  1. Cell walls break down first
  2. second, protein matrix
  3. third, the starch
66
Q

Physical changes during germination

A
  1. the grain has swelled and a
    small white chit (root cover) can be seen. If the
    husk is peeled away, the endosperm is still hard
    but getting rubbery.
  2. Rootlets appear - endosperm can be rubbed out once rootlets are at their strongest
67
Q

Rootlets

A
68
Q

Endosperm

A

the cell walls, protein matrix
and starch granules

69
Q

Germination Vessels Features

A
  • Mechanism to load and empty the vessel
  • False bottom to allow air flow
  • Fan for blowing humid air through the bed
  • Mechanism to turn the grain
70
Q

What has improved the control of germination

A

Drum maltings

Cool air can be blown through the
perforated deck into the grain bed thus removing
heat and carbon dioxide. The bed is turned
automatically by rotating the drum.

71
Q

Second main stage process of malting

A

Germination

72
Q

What is germination

A

the modification of the
endosperm and uses enzymes.

73
Q

What is measured during germination

A
  1. growth
  2. temperature
  3. moisture
74
Q

Kilning

A

heat the germinated
barley to dry it and, crucially, to stop germination.
The moisture in the grain is reduced to 4-5% prior
to further use in the distillery.

75
Q

at what stage can flavor and color be added

A

Kilning

76
Q

What does kilning do

A

It reduces some
undesirable flavours in the malt and stabilises the
enzymes, so that they can be utilised later during
mashing.

77
Q

What percentage does kilning reduce the moisture in the grain to

A

4- 5%

78
Q

two important parameters of kilning

A
  1. air on - temp entering the grain bed
  2. air off - temp leaving the grain bed
79
Q

Why are there lower air temperatures used at the
start?

A

To protect the enzyme systems in the green
malt. As the grain is dried, the air on temperature
can be increased, as the enzyme systems are
stabilised.

80
Q

Free drying

A

also known as pre break

81
Q

air off increases in temp when?

A

as the kiln time progresses and as
the grain dries, the air off has less moisture and
therefore increases in temperature. This stage is
known as forced drying (or post-break).

82
Q

Parameters monitored during kilning

A
  1. Air
    Air on and air off temperatures.
  2. Humidity
    Humidity for air off (although this is not very
    common).
  3. Moisture
    The moisture of the malt
    These parameters are determined at the end of
    the kilning process.
83
Q

is endosperm softer during kilning?

A

Yes

84
Q

What develops flavour and color

A

maillard reactions and NDMA formation

85
Q

NDMA
formation

A

formed when nitrous oxides react with
nitrogen compounds in the presence of heat)
could have occurred unless care is taken.

85
Q

Maillard reactions

A

formed from amino acids
and sugars in the presence of heat

chemical
reactions that take place in heat,
producing flavour and colour
compounds. They take place in the kiln
when temperatures reach above 160°C.
Amino acids (from the protein matrix
breakdown) react with the sugars (from
the starch breakdown) to produce colour
and flavour.

86
Q

What is NDMA

A

a carcinogenic compound
that can be formed in kilning under
certain circumstances. NDMA
formation is a bad thing in malt as
this compound has been found to
be a carcinogen and therefore has
legislative limits for spirit in some
countries. NDMA can travel through
the process into the spirit, so the
malt and the new make spirit are
routinely analysed for NDMA as a
due diligence test. Modern practices
however reduce the formation of
this compound in the malt.

87
Q

What is Peat

A

is an additive and is used to add flavour to
the malt during the kilning process. It is partially
decomposed plant material, produced in a wet
environment in the absence of oxygen. Peat can
be dug up and dried, thus becoming a fuel that
can be burned.

88
Q

How is peat described (2 ways)

A
  • Medicinal (TCP, germoline, hospitals)
  • Smoky (smoked meat, burnt wood, bonfire)
89
Q

What differentiates peat

A

Different areas in Scotland produce peat with
different active compounds, dependent upon
plant species and environmental conditions

90
Q

How much original phenolic compound ends up in the new make

A

about 1/3rd. Can be altered in the still run.

it is all about the spirit to feints cut
in the spirit still (

91
Q

When are phenols collected

A

in the later part of the heart or spirit cut

92
Q

Phenols

A
  1. heavier more medicinal phenols come off later in the run vs lighter smoke and bonfire earlier
  2. later you cut from spirit to feints, the heavier the new make
  3. Lagavulin
    and Caol Ila use the same malt so have the same
    phenol range entering the stills, but Caol Ila cuts
    off spirit earlier so has less medicinal phenols
    in their spirit than Lagavulin
93
Q

the same malt
produces an entirely different spirit due to the
spirit-to-feints cut point.

A

True

94
Q

The longer the spirit run, the more phenols in the
spirit; this also results in a lower alcohol strength
in the final spirit collected.

A

True

95
Q

too long of a spirit run can result in feinty characteristics

A

True

96
Q

How long storage for kilned malt

A

3 weeks

97
Q

why 3 weeks

A

allows for homogenization of the
analysis and allows the malt to ‘settle’.

98
Q

fiery Stills

A

A fiery still is when it is very hard to
control the level of frothing inside the
still at the start of distillation, and can
sometimes lead to carryover where froth
and solids go through the condenser into
the safe. This will cause quality issues in
the spirit. You normally get fiery stills if
the malt processed has not been rested
for at least three weeks after kilning.

99
Q

Deculmed Malt

A

Rootlets removed, done prior to dispatch

100
Q

Third main stage of malting process

A

Kilning

101
Q

Important parameters of kilning

A

air on and air off

102
Q

A flavor and coloring added during kilning

A

peating

103
Q

what adds medicinal and smoky flavours

A

Peat

104
Q

Steeps today

A

cylindroconical vessels that load
via gravity into a germination
vessel. They use compressed
air for rousing

105
Q

Drum maltings greatly improved the control of
germination

A

True

106
Q

Kilning systems have improved cost effectiveness

A

True

107
Q

Steeps use compressed air to rouse the
grain and fans to remove CO2 and heat.

A

True

108
Q

Germination vessels all have false
bottoms for air flow and a means to mix
up the grain

A

True

109
Q

Kilns are now designed to improve
efficiency such as the use of waste heat

A

True

110
Q

what system makes use of a small foot print

A

tower malting system

111
Q

what happens before milling

A
  1. malt passes through a destoner
  2. a magnet is used to remove ferrous material
112
Q

MIlling process

A
  1. The first set of fluted rollers are used to open up
    the grain, breaking off the husk.
  2. Subsequent sets of rollers grind up the
    endosperm.
  3. Beaters in between the sets of rollers remove
    husk, fine grit and flour; meaning only the larger
    grits pass through the bottom rollers.
113
Q

What is Grist

A

malt is ground into grist

Grist is made up of approximately
10% flour, 70% grits and 20% husk.

114
Q

Grist analysis

A
  1. needed for spirit yield
  2. impacts sucess of the mashing operation
115
Q

at a large efficient distillery 1 tonne malt

A

produces 415 to 420 litres of spirit

116
Q

smaller distilleries produce from 1 tonne malt

A

400 litres

117
Q

Yeast

A

a single-celled organism which feeds on sugar, producing alcohol,
carbon dioxide and heat in return.

118
Q

Yeast used for distilling

A

Saccharomyces cerevisiae

It typically has a 10 micron cell diameter
and 1,000,000,000 cells per gram.

119
Q

Yeast cell division

A

yeast propagates by budding
daughter cell to mother cell

120
Q

Anaerobic respiration

A

In the absence of oxygen, yeast metabolises sugar
to give ethanol.

121
Q

What can affect yeast

A
  1. infection
  2. alcohol
  3. sugar
122
Q

yeast strain can change the flavor profile in the wash

A

true

123
Q

what is pitching rate

A

the amount of
yeast used can also affect the congener profile by
altering the rate of fermentation

124
Q

why is wort clarity iimportant in terms of spirit character

A

a cloudy wort has the potential to give rise to a
nutty spirit, a clear wort more likely to give a fruity
or sweet spirit

125
Q

Yeast

A

one of the three raw materials
permitted for single malt Scotch whisky

126
Q

Yeast is a single cell organism which can
metabolise sugar into ethanol

A

True

127
Q

Mashing

A

he process of adding hot water to the grist

128
Q

Mashing process is filtration

A
  1. the solids form a filter bed,
  2. the liquid is filtered through this bed
  3. drains out the bottom of the mashtun.
129
Q

Purpose of mashing

A

breakdown the
starch in the grain and turn it into fermentable
sugars.

130
Q

wort

A

a sugary liquid, drained into the washback
where fermentation occurs.

131
Q

spout temperature is vital

A

it is at this point
where most of the enzymatic activity occurs.

132
Q

Optimal mashtun temperature

A

63.5C this temp balances the gelatinizatio of the starch with the enzyme activity

133
Q

Gelatinisation

A

simply means getting the
starch to become soluble in water. When
the starch swells and is hydrated, it can
be dissolved in water which allows the
enzymes access to do their work.

Would happen faster at +63.5 but would be denatured

134
Q

Enzymes at the spout

A
  1. α-amylase
  2. β-amylase
135
Q

α-amylase

A

reacts at random along the chain of the
starch molecules breaking the α-(1,4) bonds, thus
chopping up the starch. This activity reduces once
you get above 67°C.

136
Q

β-amylase

A

more selective,
releasing maltose molecules from the nonreducing
end of the starch. This enzyme is far less
stable with heat, with all activity ceasing after a
time at or above 65°C.

137
Q

secondary conversion

A

remove the wort and cool it quickly so
that the enzyme activity can be continued in the
washback;

This is vital

138
Q

limit dextrinase

A

Another enzyme

breaks
down the branches in the starch molecules, acting
upon α-(1,6) bonds, producing more straight chain
dextrins.

139
Q

where does limit dextrinase happen

A

does happen in the mashtun but
more predominantly in the washback as part of
secondary conversion.

140
Q

normal operation in distilleries now
means that all further waters are added in one
continual sparge

A

True

141
Q

Subsequent ‘waters’ are added at a higher
temperature to allow for full gelatinisation of the
starch. Higher temperatures can only be used as
adequate levels of enzymes have been removed
into the washback with the cooled wort, thus
allowing for the breakdown of the gelatinised
starch in the next stage of the process.

A

True

142
Q

Why is wort cooled between16 -20C?

A
  1. To preserve the enzymes to ensure
    secondary conversion
  2. To protect the yeast that will be added
    to the washback
143
Q

4 types of Mashtuns from older to newer

A
  1. traditional
  2. semi lauter
  3. full lauter
  4. filter
144
Q

What do mashtuns have in common 1

A
  1. Mixing grist -this must be done in such a way as
    to fully hydrate the grist thus leading to maximum
    starch gelatinisation and commencing the
    hydrolysis of the starch molecule
145
Q

Mashtun common 2

A
  1. Additional water -

Additional water must be able to be added into
the tun and the resultant liquid (wort) must be
able to be removed or pumped. The wort must be
cooled after draining through the slotted floor and
false bottom in the tun.

146
Q

Mashtun commonalities 3

A
  1. Stirring or slicing -
    Each type also needs a mechanism for stirring
    or slicing through the bed, to allow for increased
    drainage.
147
Q

mashtun commonalities 4

A
  1. Draff removal
    Each type of mashtun must have a system
    designed to remove the left over draff. can be simple but now usually automated
148
Q
A
149
Q

in-place cleaning

A

New progression in mashtun design

an automated system
cleans in the tun and under the floor, normally
with hot caustic; thus removing the need for
operator entry.

150
Q

other developments in mashtun technology

A
  1. Temperature probes are now much more
    accurate and reliable, thus leading to
    improved efficiency and constancy.
  2. Automation, along with computer control,
    has improved levels of consistency and
    further reduced operator requirements.
  3. Development in pumping control has
    removed the requirement for an underback
    and many sites now pump directly to
    the washbacks.
151
Q

traditional mashtuns are associate dwith

A
  1. distilleries with visitor centers, ie springbank
  2. a cloudy wort due to the continual break up
    of the bed by the rakes or paddle
152
Q

semi-lauter

A

have to stop
pumping while extra water is added.

referring to mashtun operation - the arms and knives are at a fixed
height.

153
Q

full lauter

A

water can be added as
wort is removed,

referring to arms in mashtun operation - the arms and knives can be raised
and lowered.

154
Q

What is a mashtun made out of

A

cast iron or stainless steel

155
Q

The bottom is effectively a sieve which
allows the sugary liquid – wort – to drain
through to the underback (if there is
one) and then onto the washback where
fermentation occurs

A

True