Mod 3 Raw Materials Flashcards
All water used during the production process in the Scotch whisky industry is
derived from
Rain or snow
The basic requirements of
water supply are that it is
adequate and available
water sources
- springs
- burns/rivers
- lochs
- wells
- boreholes
- mains
Water is used in several key phases of the
production process (3)
- steeping & mashing - ph microbiological purity
- cooling - volume temp
- dilution - ph,hardness, volume, temp, microbiological content.
why is it good to know the mineral content and ph balance of water when steeping and mashing
steeping and mashing are
basically biochemical processes, they can be
affected by the mineral and ion content - and by
the pH - of the water.
Why know hardness level
The mashing water used can influence the
fermentation, depending upon the hardness levels
and ions present.
soft water
heavier new make
Harder water
cleaner/sweeter new make
spirit
Cool Water
cool water is required for the
condensers, therefore the quality parameters here
are simply volume and temperature
Dilution
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.
Once sourced, that water is used at four
key parts of the production process
steeping, mashing, cooling & dilution.
Main raw material in the production of single malt
Barley
Malting barley moves through 3 key stages in the pre production process
- growth & harvesting,
- variety development
- testing
Growth and harvesting
- malting barleygrown predominately on east side of uk
- lower rainfall than the west
3 . preferable soil - 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
Variety development
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
Shape of grain
Is it bold, thin, or flat
Rachilla
a structure in the ventral crease, can be short or long.
Can have hairs that can be short and wolly or long and straight
what maltsters like in malting barley
Cost effective
* Bold grain
* Appropriate nitrogen level
* Good germinative ability
* Varietal purity
* Reliable supply
* Suitable storage
Best malting barley
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.
Homogeneous Malt
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.
Agriculture and
Horticulture Development Board (AHDB).
Testing and breeding system in the UK
produces a recommended lists of barley varieties
and recommends those to use in the various
industries.
Agriculture and
Horticulture Development Board (AHDB).
Testing is done
prior to maltsters buying barley
5 test on barley
- Nitrogen
- Moisture
- Screenings
- Germination
- Varietal purity
Reference method for nitrogen
Dumas method
Near Infrared (NIR) equipment
equipment that most analysis is carried out on
barleyis dried because
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).
Insects cannot breed in what temps
(insects cannot breed in barley if it is less than
15°C and less than 12% moisture
recognized industry levels for barley temps and moisture during storage are
are less than 12% moisture
& 15°C.
how is barley dried
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 is barely stored
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.
barely is stored
in a silo or flat store
steeping
raising the moisture level to such an extent that
germination is initiated.
barely is dried prior to storage because
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
Dormancy
is the natural tendency
to inhibit germination, and can vary
depending upon variety, growing
conditions and harvesting conditions.
self-emptying cylindroconical vessel
very water efficient compared to false bottom
flat steeps, used for steeping
level of hydration in grain dependent on
Water temperature
* Grain size
* Variety
* Viability
Water temperature
Higher water temperature
results in more rapid water
uptake and may be required if
the grain is less mature
Grain size
Larger grains require more
time under water to reach
the same moisture level as
smaller grains.
Viability
The maturity (or viability)
of grain also affects water
uptake, with the barley
taking in water more
quickly as it matures.
Variety
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.
Multiple Steeping
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.
What is multiple steeping
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.
Target moisture at the end of steeping
the mid-40s but the actual figure is dependent
upon the type of malt being made.
higher steep out or cast moisture
result
in increased respiration and therefore increased
malting loss. It will also result in increased enzyme
activity and soluble nitrogen content.
Cast moisture
is the moisture level in the
grain as it is moved from the steeping
stage to the germination stage.
Cast moisture
- the more water, the
more active the grain, until you get to the
stage where it will drown. - The more active the grain, the quicker
the breakdown processes inside the
grain;
Hydrolysis
the technical term for the
breakdown of starch into sugars.
Germination physical changes
After water intake, the grain has
swelled and a small white chit (root cover) can be
seen.
Chemical Changes
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.
Germination
produces the enzymes required for
the hydrolysis process. And distillers want the
starch and the enzymes
Structures in barley grain related to germination
- Micropyle
- Embryo
- Endosperm
- Husk
Germination
Embryo
the living part of the grain,
sometimes called the germ; it is the ‘baby’ plant.
Micropyle
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.)
Husk
the ‘skin’ that surrounds and protects
the barley.
Endosperm
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.
Endosperm during germination
altered due
to the action of enzymes.
what does the embryo release at the start of germination
a
hormone called Gibberellic Acid, known as GA3.
MOdification Front
This initiates the aleurone layer to release
the enzymes required to break down the cell
walls, protein matrix and starch granules.
Modification front breakdown occurs
from the embryo end to the
distal end of the grain.
Malting Loss
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.