Modern Bourbon Production Methods Flashcards
Whiskey is made from a fermented mash of ______________.
Grains
What grains are the most common for whiskey production?
Barley
Corn
Rye
Wheat
Others include:
Oats
Quinoa
Hybrid grains like triticale and buckwheat
What is malting?
Natural process designed to trick the grain (often barley) into thinking it is spring-time so it will sprout are release enzymes that convert starch to sugar
Three steps:
1) Steeping
2) Germination
3) Kilning
Steps in making whiskey
1) Grow grain
2) Harvest/Clean
3) Malt (sometimes)
4) Grind/Mill
5) Mash/Cook
6) Ferment
7) Distill
8) Age
9) Blend (often)
10) Bottle
What is the “mother grain” for Scotch Whisky?
Malted Barley
Barley is relatively easy to malt - which creates enzymes necessary to convert starch to sugar - not just in barley, but other grains as well
What is the part of the barley corn that holds it’s starch reserve?
Endosperm
When was the first physical evidence of malting barley?
4000 BCE in Mesopotamia
What are the three steps in MALTING barley?
Steeping
Germination
Kilning
What is STEEPING?
Barley corns are exposed to alternating water and heat for around two days until it is allowed to germinate
What is GERMINATION?
After steeping for around two days, the barley sprouts - releasing the enzyme necessary to break down the protein net and expose starches. Before the shoot begins to consume a significant amount of food, the barley is kilned
What is KILNING
Heating the malt to stop the process of germination and dry the barley so it can be stored until needed.
The grain is put in a kiln and hot air blows through it - drying it and killing the sprout.
What is peat? And what is it used for in malting process?
Peat is decaying moss (mostly sphagnum) that has built up over centuries in bogs that is harvested and used to flavor whiskey (usually in Scotland).
How is peat used as a flavoring agent for certain Scotch Whiskies?
-Peat is harvest from the ground, dried and then burned.
-It used to be used all over Scotland as the actual fuel to produce the hot air to dry out barley during kilning
-Now it is burned in a furnace next to the actual heat source and the peat flavored smoke (peat reek) is blown through the grain to flavor the barley while drying
How long does it take to dry barley in a kiln?
Usually about two days to dry the barley.
When peat is used for flavoring it is used for up to the first 18 hours
Who brought Rye to North America and started using it to make both bread and whiskey?
German emigrants brought rye to North America in the 1700s, and the knowledge of how to distill it
What is Malt Whisky? and what are the main countries known for making it?
Malt Whisky (sometimes refered to as Single Malt Whisky) is made from 100% Malted Barley
Scotland, Japan, some Irish, and some American
What is Grain Whisky? and what are the main countries known for making it?
Grain Whisky is made from varying grains, often wheat. There is often at least a small portion of malted barley in the mix (for the enzymes).
Scotland, Japan, some Irish
What is Rye Whiskey? and what are the main countries known for making it?
Rye whiskey is made from 51+% rye plus malt & corn
This is the US definition, there are also Rye Whiskies made in Canada from very little, up to 100% Rye
What is Bourbon?
-Made from at least 51% Corn + malt + either rye or wheat
-Bourbon must the made in the US
-Bourbon must be distilled to no more than 160 proof (80% ABV)
-Bourbon must be aged in new, charred, oak barrels
(those barrels are usually American White Oak, but do not have to be by law)
Which grain is the most prominent grain for whiskey production in North America?
Corn is king in North America
Also called Maize in many places in the world
What are the characteristics of CORN that make it good for distillation?
-Incredible fecundity (ie produces a HUGE amount of grain in right conditions)
-once corn has been milled and cooked to split open starchy matrix, it takes a relatively small amount of malted barley to convert corn’s plentiful starches into sugars
-Corn’s only problem is that it is a bit of a one-trick pony = the flavor is sweet and strong
Why is the combination of corn + malted barley + either rye or wheat so appropriate for making Bourbon?
CORN = plentiful, lots of starch (but not easy to malt), not a lot of flavor
MALTED BARLEY = just a little malted barley provides enough enzymes to convert the starch from ALL the grains into sugar
RYE or WHEAT = used as “flavoring grain” to create the targeted flavor profile (Rye = spice, Wheat = soft and creamy)
What is the process for cooking the mash, once
What is the cooking order for various grains in a Bourbon mash bill?
1) Corn is cooked at 194-212F
2) then temp lowered to 158F to cook Rye (wheat is similar temp)
3) then temp lowered to 147F to cook Malted Barley to convert starch to sugar
What is SOUR MASH?
a small amount of stillage/backset (which is acidic residue that is left in the column still after distillation is added to the next fermentation to create acid balance, help yeast propagation, and prevent bacteria from growing during fermentation. This creates continuity and consistency.
What percentage of sour mash is added to each fermentation run?
It varies by distiller, but up to 33% of a fermenter is filled with backset
What components of fermentation have an effect on aromas and flavors produced?
1) yeast strain (most distillers in American whiskey production use a proprietary yeast strain)
2) speed of fermentation
3) length of fermentation
4) temperature of fermentation
how long do American whiskey fermentations last?
-Average 3-4 days to get to around 8% ABV for short ferment and 12% for long ferment
What types of stills are used for whiskey distillation?
1) Pot Stills
2) Column Stills
3) Hybrid Stills
4) extractive distillation stills
Pot still distillation
-Batch process
-usually at least 2 distillations
-FIRST distillation raises overall ABV of the entire solution
-SECOND distillation makes cuts to HEADS, HEARTS, and Tails
What are the boiling temperatures of ethanol and water?
-Ethanol = 173F / 78C
-Water = 212F / 100C
How does the angle of the lyne arm coming out of a column still affect the distillate?
1) Upward facing lyne arms allow more reflux (contact between vapor and liquid) to happen because vapors can continue to condense and fall back down the still for a longer period of time = cleaner spirit
2) horizontal or downward facing lyne arms create less reflux
What is REFLUX?
Reflux refers to the amount of vapor that condenses back into liquid and falls down the still - and coming in contact with vapor rising up the still - more reflux = cleaner, lighter spirit vs less reflux = heavier, oilier spirit
Why is copper so important in still design for distillation?
Copper removes sulphur and therefore the meaty, almost cabbagey smells
What are the “foreshots” or “heads” and what happens to them during the (second) distillation?
Foreshots/heads include methanol, acetaldehyde, ethyl acetate, and acetone. All of which create off flavors and can be dangerous in large quantities. They are separated from the hearts of the distillate and recycled with the feints/tails back into the “next” distillation.
What are the “hearts” of the distillate?
Ethanol
Propyl Alcohol
Congeners
Water
these move on to maturation to become the final spirit
What are the “feints” or “tails” of the distillate? And what happens to them?
Butyl alcohol
Acetic Acid
Amyl Alcohol
Furfural
*sometimes collectively referred to as “fusel oils” these are recycled along with the foreshots/heads into next distillation
What are LOW WINES in Bourbon production?
In Bourbon production, the low wines are usually around 20% ABV and will then be distilled again in a smaller spirits still.
What is the difference between pot still and column still distillation?
Pot still distillation is a batch process. Column stills run continuously and are therefore more efficient.
What is the maximum distillation proof for Bourbon?
Bourbon must be distilled to no more than 160 Proof (80% ABV)
What type of column still is used for Bourbon production? How does it work?
Bourbon is usually produced in a Beer Still (with either a Doubler or Thumper attached).
The key to the Beer Still is that wash (or beer) falls as liquid down the still and meets steam rising up the still on several perforated distillation plates. On each plate REFLUX happens and the more volatile compounds are stripped from the liquid and rise up the still. The less volatile compounds become liquid and fall down the still. The higher the vapor rises up the still, it becomes more concentrate with alcohol. The vapor is collected towards the top of the still at no higher than 160 proof. It then flows into a second still (a pot still called either a Doubler or a Thumper).
How does a Bourbon Beer Still differ from a Coffee Still used to make grain whisky in Scotland?
There are a few differences:
1) a Coffee still has two columns - an analyzer and a rectifier. The wash is introduced at the top of the analyzer which works similar to a Beer still and “strips” alcohol vapor. The vapor then flows into the bottom of the rectifier. Vapor flows up the rectifier, coming in contact with liquid that creates more reflux and concentrates the alcohol vapor.
2) Because a Coffee Still has two columns, it concentrates alcohol to a higher ABV (usually around 90%) which creates a cleaner, purer spirit.
3) Solids are filtered out of the fermented liquid before it enters a Coffee still. Beer stills are filled with wash that includes solids (sort of a porridge consistency) - the solids are removed from the bottom of the Beer still.
Describe barrel CHARRING.
Charring is placing an open-ended barrel over a burner and blowing a hot flame into it. This literally sets the inside of the barrel on fire (for somewhere up to 45 seconds and transforms that barrel “from a mere container to a chemical reaction chamber, a filter, and an infusion vessel.”
What does charring do to wood?
1) Creates a layer of charcoal on the inside of the staves (creates a filter and expands surface area
2) heat of charring also changes oak beneath the char - sugars in the wood are carmilized creating the “red layer”
3) Breaks down the oak’s LIGNIN
What is LIGNIN?
Lignin is a natural polymer in wood, a big complex molecule that adds strength to the wood.
As alcohol breaks down lignin in wood it creates flavor compounds like vanillin, wood aldehyde compounds, and aromatic esters.
What are three major esters formed by breaking down oak lignins during maturation?
Ethyl Syringate (tobacco and fig)
Ethyl Ferulate (Cinnamon)
Ethy Vanillate (Smokey burn aroma)
What is meant by “Breathing” barrels?
Slow exchange of air and liquid steals away up to 5% per year (angel’s share)
As barrels age in Scotland vs US, what happens to the ABV inside the barrel?
Scotland - loses more alcohol than water in cool, humid conditions that are realatively constant year-round. ABV goes DOWN
US - loses more water than alcohol in hot, dry conditions that are variable over the course of the year. ABV goes UP
(a whiskey may go in at 120 proof and come out at say 135 proof 7 years later - stronger ABV but reduced in volume)
What are TYLOSES in oak?
Tyloses are blockages in the woody outer layers of the tree. Tyloses serve to cut losses of living tissue during drought or infection. For the cooper, Tyloses are what make the oak a favored wood for waterproof barrels.
They do allow air flow - so water tight, but not air tight.
What are chemical reactions inside the barrel that are aided by air flow?
1) Char breaking down lignin and subsequent development of various compounds
2) Compounds in whiskey mixing with incoming air - oxidation
3) Creation of fruity esters = signature aromatics
What is industry standard size for American Whiskey Barrels (ASBs)?
53 gallons (just over 200 litres)
What size barrels to smaller (newer) distillers sometimes use to attempt to “speed up” the aging of their whiskey?
30 gallon, 15 gallon, 5 gallon, even 2 gallon
These barrels often impart oak flavors and dark color - but do not provide “maturity”
What are the flavors most associated with Bourbon barrels?
Vanilla and Coconut
What is the difference between an American Standard Barrel and a Hogshead - and how are hogsheads made?
Once used, American Bourbon barrels are often sold to Scottish Distilleries.
They are broken down into staves and hoops for shipping.
When they arrive in Scotland, they are often re-assembled with more staves and new heads.
A hogshead is 225 litres (63 gallons in size)
How do warehouses provide American Whiskey producers variety in casks even though they are all new wood?
Warehouse location in a seven-story “Iron clad” warehouse can provide huge swings in heat depending on which floor a barrel is located.
Higher floors - more heat “faster” maturation
Lower floors - less heat “slower” maturation
Middle floors - where barrels are surrounded by lots of barrels = most consistent
Final product is often a blend of many different locations to create consistent style
Do all whiskies have age statements?
No
What does age statement represent?
Age statement is the age of the youngest liquid in the bottled blend.
Once the whiskey leaves the barrel - the aging is over.
What are some of the factors that determine higher pricing for older whiskies?
*It’s important to remember that there are really only two things that effect the price of anything = supply and demand. However,
1) there aren’t many barrels that will make it to the extremes of age
2) Evaporation and Angle’s Share - the older the whiskey, the less is left in the barrel
3) Rarity
What is MARRYING in regards to whiskey aging and bottling?
The contents of barrels are mixed and then often placed in a large wooden vat for a length of time to allow the whiskey to “marry” before bottling.
What is CHILL FILTERING?
When whiskey gets very cold, down around the freezing point of water, there are some proteins that will precipitate, turning the whiskey hazy.
Many producers will purposely chill the whiskey down before bottling and filter out the haziness - so it doesn’t appear hazy to consumers after purchase.
According to the Bryson book, what are the three most important categories of American Whiskey?
Bourbon
Tennessee Whiskey
Rye
lesser known types include
Corn Whiskey
Wheat Whiskey
Blended Whiskey
Spirit Whiskey
What are the US regulations that govern whiskey (really all spirits) called?
The Standards of Identity… and officially in the Standards of Identity - American Whiskey is called Whisky.
Specifically, where do the Standards of Identity for Whiskey reside?
US Code of Federal Regulations
Title 27 (Alcohol, Tobacco & Firearms)
Part 5 (Labelling and Advertising of Distilled Spirits)
Subpart C (Standards and Identity for Distilled Spirits
Paragraph 22
What is the US government agency that is responsible for approving and enforcing labeling and other liquor laws?
The Alcohol and Tobacco Tax and Trade Bureau (ATTTB or TTB)
What are the three parts of the Standards of Identity for Whiskey in US?
1st - Identifies Whiskey
2nd - deliniates two classes of whiskey
-Corn
-Bourbon, Rye, Wheat, Malt, Rye Malt
and now American Single Malt
(ASM won’t be included on exam)
3rd - makes further definition of “straight”
whiskey
What is the definition of Whiskey according to the US Standards of identity?
