Malt Whisky Production

Question 1

Most Single Malt Distilleries use SOFT water, what distilleries are exceptions to that rule?

Answer 1

Glenmorangie, Glenkinchie, and Highland Park are famous distilleries that source HARD water.

Question 2

What are the two most important components of water used for Single Malt Scotch production?

Answer 2

The water needs to be ABUNDANT and PURE

Question 3

What are the important characteristics quality barley for Scotch Whisky production?

Answer 3

1) High starch content
2) Low protein content (less than 1.5%)
3) low nitrogen content (less than 1.7%)
4) High likelyhood of germination
5) Easy to process
6) Well-ripened, plump and dry.

Question 4

According to the text, what percentage of barley used for malting comes from Scotland?

Answer 4

Scotland = 75%
England = 15%
Overseas = 10% (France and Denmark)

Question 5

Yeast is “pitched” at what % of the weight of the malt mashed?

Answer 5

2.2%

Question 6

How long does fermentation take to create ethanol?

Answer 6

48-50 hours. Longer fermentations lead to ester creation

Question 7

The primary by-product of fermentation is ethanol. What other compounds are created (in small amounts)?

Answer 7

Congeners (including a wide range of esters, aldehydes, acids, and higher alcohols which contribute to flavor.

Question 8

What are the three parts of malting?

Answer 8

Steeping
Germination
Kilning

Question 9

What is the part of the barley corn that would become the new plant if it was allowed to grow?

Answer 9

Embryo

Question 10

What part of the barley corn is the store of starch to fuel the growth of the plant

Answer 10

Endosperm

Question 11

What is the moisture content of barley that is considered dry?

Answer 11

Less than 12%

Question 12

During steeping the moisture content of the barley must be raised to _____%?

Answer 12

46%

Question 13

What is the term used for malted barley once it has completed the germination phase?

Answer 13

Green Malt

Question 14

Name some Single Malt Distilleries that have their own malting floors

Answer 14

(Mentioned in book)
Balvenie
Bowmore
Laphroiag
Highland Park
Springbank (100%)
Glen Ord

(also)
Ardross
Ben Riach
Glen Garioch
Kilchoman

Question 15

Other than floor maltings, name two systems used for malting barley

Answer 15

Rotary Drums
Steep, Germinate, and Kilning Vessels (SGKV’s)

Question 16

How long in the kilning phase for malting barley?

Answer 16

The whole kilining process takes between 20 and 48 hours.

Question 17

What is peat?

Answer 17

Peat is acidic, decayed, vegetation made from bog plants such as sphagnum moss, heather, sedges and grasses that forms in a non-oxidative (under water) environment in peat bogs.

Question 18

Intensity of peating falls into three broad categories, what are they and what are the ppm ranges?

Answer 18

Lightly peated = 1-5ppm
Medium peated = 10-20ppm
Heavily peated = 30-50ppm)

Question 19

What is name of the vessel where mashing takes place?

Answer 19

Mash Tun

Question 20

What is the liquid called after mashing?

Answer 20

Worts

Question 21

What are the temperatures for the (usually) three mashing waters?

Answer 21

1st water = 63-64 degrees
2nd = around 70 degrees
3rd = around 85 degrees

Question 22

How much alcohol is expected to be extracted from each ton of malt?

Answer 22

420 Litres (92 Gallons)

Question 23

How many distilleries have worm tub condensers?

Answer 23

15 distilleries (according to MacClean text)

Question 24

Pot stills come in three basic designs. Name them?

Answer 24

Plain or Onion
Latern
Boil Ball

Question 25

What distillery has the tallest pot stills in Scotland?

Answer 25

Glenmorangie

Question 26

Name some still things that can increase reflux in a pot still?

Answer 26

Purifiers or return pipes
Angle lyne arms upward

Question 27

What substance removes sulphury and vegetal components?

Answer 27

Copper. Generally, the smaller the still, the greater surface area of copper put unit of distilled vapor.

Question 28

How are a vast majority of the pot stills in Scotland heated?

Answer 28

Most are indirect heated using steam coils. (Springbank distillery still uses direct fire to heat their stills.)

Question 29

What is the purpose of the first distillation in the double distillation process?

Answer 29

The first distillation raises the overall ABV from about 8% ABV up around 21% ABV. There are no “cuts” made from the first distillation. At the end of the first distillation we have what are referred to as “low wines.”

Question 30

What is the purpose of the second distillation in the double distillation process?

Answer 30

During the second distillation we will make “cuts” separating the low wines into “foreshots” (or heads), “spirit” (or hearts) and “feints” (or tails). The hearts at the end of the second distillation will be captured in a condenser as “new make spirit” that will move on to maturation. The foreshots and the feints will be recycled into the low wines from next distillation and re-destilled.

Question 31

How long must new make spirit be aged before it can be called whisky?

Answer 31

Scotch Whisky must be aged for a minimum of three years, in OAK barrels, that are no larger than 700 Litres.

Question 32

Prior to barrel filling, the new make spirit is diluted to what ABV?

Answer 32

63.5% (there are exceptions, but this is the norm).

Question 33

What are the main factors that will impact maturation?

Answer 33

The nature of the cask (what type of oak - usually ex-Bourbon or Ex-sherry)
The size of the cask (200L ASB, 250L Hogshead, 500L Sherry Butt)
The history of the cask (ex-Bourbon, ex-Sherry) / 1st fill, 2nd fill, etc.
The style of the warehouse (Dunnage, Racked, Palatized)
The geographical location where the barrel is aged
The microclimate where the barrel matures
The length of maturation

Question 34

What is Quercus Alba?

Answer 34

American White Oak. Usually imparts sharp, terpintine, or pine aromas to whisky.

Question 35

What is Quercus Robur?

Answer 35

A species of European Oak. Usually imparts resinous, fruit cake aromas to whisky.

Question 36

What are some of the substances that oak contains making it ideal for aging whisky?

Answer 36

-Oak contains cellulose, hemicellulose, lignin, tannins, and wood extractives.

Question 37

What does the hemicellulose in oak contribute to whisky?

Answer 37

Hemicellulose caramelizes, adding sweetness and color

Question 38

What does the lignin in oak contribute to whisky?

Answer 38

Lignin is a good blending agent, pulling flavors together, increasing complexity and producing vanilla like notes.

Question 39

What do the tannins in oak contribute to whisky?

Answer 39

Tannins produce astringency, fragrance and delicacy.

Question 40

How does oxidation impact whisky as it matures in an oak barrel?

Answer 40

Oxidation removes harshness, increases fruitiness and adds complexity.

Question 41

How does the charring of casks impact whisky as it matures in an oak barrel?

Answer 41

Charring the casks removes undesirable off notes as it creates a filter that the whisky passes through during aging.

Question 42

What are the most popular type of oak barrels used for maturing whisky in Scotland?

Answer 42

Since 1946, ex-Bourbon casks have become the most popular and now represent around 90% of the casks coming into the system.

Question 43

What are the two categories of Ex-Bourbon Casks used for aging Scotch Whisky?

Answer 43

American Standard Barrels (ASBs) are usually 180-200 liters and are often transported whole from American to Scotland.

Hogsheads are 250 liters and are created by breaking down ASBs, transporting the staves to Scotland and then re-assembling them with new heads. Five ASBs, create three Hogsheads.

Question 45

What are the two most common types of Ex-Sherry Casks used in Scotch Whisky maturation?

Answer 45

Although any size cask may be seasoned with sherry, Sherry Butts and Sherry Puncheons are both 500 Liters. Butts are taller and narrower, Puncheons are more squat and broader.

Question 46

What are the three vital functions performed by the cask during maturation?

Answer 46

There are three “mechanisms” performed by the cask during maturation. The ADDITIVE mechanism adds desirable flavors to the spirit, the SUBTRACTIVE mechanism removes unwanted flavors, and the INTERACTIVE mechanism allows the spirit to interact with its environment, losing harsh alcohols and developing complexity through oxidation.

Question 47

What is toasting? And how does it impact whisky barrels?

Answer 47

Toasting is a process of heating the inside of a barrel and thereby altering the chemical structure of the inside of the barrel. Toasting degrades hemi-cellulose, and lignin in the wood that produce caramel, vanilla and coconut flavors that can then leach into the spirit. Toasting can also have a significant impact on the whisky’s color.

Question 48

What is charring? And how does it impact whisky barrels?

Answer 48

American Oak Barrels used for Bourbon or Tennessee Whiskey production must be charred by law. This charring is the process of actually setting the inside of the barrel on fire creating a charcoal layer. This charcoal layer forms a useful “purifier” or “filter” that removes immature characteristics and unwanted compounds (mainly Sulphur) from the whisky. Some barrels are toasted before they are charred. Some barrels are only charred (which is the part that is required by American law).

Question 49

What is the difference between a “first fill” and a “re-fill” cask?

Answer 49

A vast majority of casks used for maturing Scotch Whisky are barrels that have been used to mature something else already (ex-Bourbon, ex-Sherry, etc.). The first time they are re-used to age Scotch, they are referred to as “first-fill,” First-fill casks tend to be to be much more “active” and will impart significant flavor. For longer maturation, distilleries often want to use “re-fill” casks which have been previously used to age Scotch because they are less “active.”

Question 50

How many times will a Scotch distillery typically use a “re-fill” cask?

Answer 50

Many Scotch distilleries will use re-fill casks three or four times. Then they can “refurbish” casks by a process called “de-char, re-char” where the inside of the cask is scrapped and then re-charred. This varies by distillery. As an example, it is Macallan’s policy to use a cask no more than twice (ie. once as a “first-fill” and then once as a “re-fill”)

Question 51

What are the three most common types of warehouse used for maturation for Scotch Whisky?

Answer 51

DUNNAGE warehouses are low, stone-built, with earthen floors - casks are racked three high.
RACKED warehouses are much larger, temperatures are often mechanically controlled and casks are stacked up to 12 high.
In PALLITIZED warehouses the casks are stored standing up on pallets rather than laying on their sides as they would be in dunnage or racked warehouses.

Question 52

What is the “Angels’ Share?”

Answer 52

Based on the temperature and humidity in the warehouse where whisky is aging, a whisky cask will lose somewhere around 2% of it’s contents per year to evaporation. This is called the “Angels Share.”

In Scotland, due to temperature and humidity, ABV will DECREASE as the whisky matures because ethanol evaporates slightly faster than water. Conversely, in a dry, warm climate like Kentucky, ABV will INCREASE as the whiskey ages, because water evaporates slightly faster than ethanol.