Alcohol can be produced through fermentation and distillation processes. There are two main distillation methods - pot still distillation and patent still distillation. Pot still distillation is slower and involves multiple distillations to produce spirits like scotch and rum. Patent still distillation uses a continuous column still for a more controlled process that requires only one distillation to produce spirits like bourbon and gin. Alcoholic strength is measured using various scales throughout history from traditional methods to modern scientific scales like Sykes hydrometer and OIML scale, which express alcoholic strength as a percentage of alcohol by volume. Common alcoholic beverages and their typical alcohol contents are also outlined.
3. Introduction
• Alcohol is a word derived from word al – kohl (Arabic). Kohl is black,
very fine staining powder which is used cosmetically – once for
staining the eyelids of Harem Beauties. Later the name wasn’t applied
to highly refine chemical powder and essences and then Spirits
produced by distillation and rectification.
4. Definition
• Alcohol is a volatile mobile fluid obtained by fermenting a liquid
containing sugar, the strength of which can be further increased by
distillation. Although there are various kinds of alcohol, the main ones
are Methyl alcohol (CH3OH, Methanol) and ethyl alcohol (C2H5OH,
ethanol).
5. History
• The Bible says that wine is the choicest gift of God to mankind;
• The Christ said that wines are blood of grapes.
• The alcoholic beverages have spiritual connotations taken to divine
heights by most religions except Islam which strictly prohibits it.
6. CONTD...
• Bacchus was considered to be the God of wine by Greeks.
• Another important story that goes on discovery of wine narrates an Egyptian
king being fond of grapes, stored grapes in wooden barrels in underground
cellars.
• Some of barrels started emanating foul smell, which was marked poison to
prevent any from accidently consuming.
• One of the queens was fed up of life, had some of the liquid to kill herself.
• However, she lost the desire to commit suicide and felt better day after day by
consuming the same and soon got addicted to it.
• Ultimately the king discovered this and tried out the liquid himself. Thus the
wine was born.
7. Fermented Brewed & Fermented Fermented and Distilled compounded
Wine (Table, Sparkling,
Aromatized, Fortified
Wine
Beer Spirits ( whisky,rum, gin,
vodka, tequila, brandy.
Liqueurs ( Drambuie,
Kahlua, Tia Maria, Malibu,
etc.)
Cider Sake Eaux-de-vie ( fruit
brandies, Applejack,
Calvados, Etc.)
Vermouth
Perry Bitters
Classification of Alcoholic Beverage
8. Fermentation Process
• Ethanol fermentation, also referred to as alcoholic fermentation,
• Is a biological process in which sugars such as glucose, fructose,
and sucrose are converted into ethanol and carbon dioxide as
metabolic waste products.
• Because yeasts perform this conversion in the absence of oxygen,
ethanol fermentation is classified as anaerobic.
• C6H12O6 + Zymase → 2C2H5OH + 2CO2
• C2H5OH is the chemical formula for ethanol.
9. Distillation Process
• Distillation is a method of separating two liquid mixtures based on
the difference of their boiling point.
• Distillation is a unit operation, or a physical separation process, and
not a chemical reaction.
• A simple formula for fermentation is:
YEAST + SUGAR (C6H12O6) = ALCOHOL + C02
10. Pot Still Distillation
• Originated in the middle ages....
• Slow, low temperature distillation..
• The pot still is shaped like a giant onion and consists of 02 parts:-
1. A still
2. Worm condenser
• The still is made of copper
• The worm condenser is a spiral tube.
• Alcohol boiling temperature: - 78.2ᵒC
12. • As the alcoholic wash boils, vapours pass up the neck of the still and
then pass through a water cooled condenser or a worm, a coiled
copper pipe of decreasing diameter enclosed in a water jacket
through which cold water circulates. This condenses the vapours and
the resulting distillate, known as low wines, is collected for re-
distilling.
• The low wines are distilled again in the Spirit Still, similar in
appearance and construction to the Wash Still but smaller because
the bulk of liquid to be dealt with is less. Three fractions are obtained
from the distillation in the Spirit Still. The first is termed foreshots
(head), the second constitutes the potable spirit (heart), and the third
is called feints (tail). The foreshots and feints are returned to the
process and redistilled in the Spirit Still with the succeeding charge of
low wines. The residue in the still, called spent lees, is run to waste.
13. Patent Still/Column Still/Continuous Still
• A patent still distillation is a method of producing grain whiskey
through a continuous distillation process.
• It is also called a “Coffey” still, from the name of Aeneas Coffey, who
patented the idea in 1831.
• The first column (called the analyzer) in a column still has steam rising
and wash descending through several levels.
• The second column (called the rectifier) carries the alcohol from the
wash,where it circulates until it can condense at the required
strength.
15. • . Steam is fed into the base of the analyser and hot wash into the top.
As the two meet on the surface of the perforated plates, the wash
boils and a mixture of alcohol vapours and uncondensed steam rises
to the top of the column. The spent wash runs down and is led off
from the base.
• The hot vapours enter the rectifier at the base and as they rise
through the chambers they partially condense on the sections of a
long coil through which wash is flowing. The spirit vapour condenses
at the top of the rectifier and is run off through a water cooled
condenser to the spirit safe and on to the spirit receiver. Once the
spirit begins to be collected it runs continuously until the end of
distillation.
16. Difference
Pot still Method
This is uncontrolled method of distillation.
Double or triple distillation is required to
obtain marketable product.
This is one of the oldest methods of
production of spirit.
Maturation is required for the product
obtained through this method.Spirit obtained
through this method has a less alcoholic
content.
Needs cleaning after every boiling.
Spirit made by this method contains
impurities.
For example – Scotch whisky, Irish Whisky,
Dark Rum, Cognac etc.
Patent still Method
This is controlled method of distillation.
Only one distillation is required to obtain
marketable product.
This is a new or modern method of
production of spirit.
No maturation is required for the product
obtained through this method.
Much stronger spirit is obtained has a higher
alcoholic content.
It does not require repeated cleaning after
every boil.
Nearly all impurities are removed to give
pure spirit.
For example – Bourbon whiskey,
Tequila,Gin,light Rum etc.
17. Alcoholic Strength
• The concentration of alcohol in an alcoholic beverage is called its
alcoholic strenght.
• There are 02 methods of measuring alcoholic strenght.
• Traditional or Primitive Method
• Scientific Method
18. Traditional/Primitive Method
• Gun Powder: To test alcoholic strength initially distillers mixed equal
quantities of Spirit with gun powder and applied a flame to it. if the
mixture failed to ignite, the spirit was too weak and if exploded or
burned too brightly, it was called too strong. But if it burned with mild
blue flame, it was proved suitable and safe for drinking.
19. Clarke's Float
• In the 17th Century, Clarke's invented a weighted float. when this
float was dropped into a spirit, the dept to which it sink determines
the density of the liquor and the alcoholic strenght could be
calculated from this.
21. Skyes Hydrometer
• In 1816, Skyes introduced Skyes Hydrometer, Skyes
determined that 100ᵒ was proof and that pure
alcohol was 175ᵒ (75ᵒ OverProof)
• On this scale, the figure for pure alcohol is 13/4
times the figure accorded to proof spirit.
• In another word 100ᵒ Proof equals 57.1% alcohol
and 42.9% water.
• The system also called British system became
traditional through out the United Kingdom.
• The liquor were sold potable of 70ᵒ Proof (30ᵒ Over
Proof).
• To convert the British Proof into percentage by
volume of acohol, simply multiply the proof by four
(4) and divide by seven (7).
• 70X4/7=40%
22. Gay-Lussac System
• Gay-Lussac (1778-1850) invented this system. Applied throughout
Europe.
• In Gay-Lussac or GL system 0ᵒ is the absence alcohol and 100ᵒ
Pure alcohol.
• The alcoholic strenght is measured at 15ᵒC.
23. American System
• American created their own sytem , reasonably logical.
• Proof spirit was an exact balance of alcohol and water and that pure
alcohol is 200ᵒ Proof.
• Each degree of Proof equal one-half percent of alcohol. So a
spirit marked at 90ᵒ Proof would contain 45% acohol by volume
24. OIML Scale
• The Organisational Internationale de Metroloqie Legale (OIML).
• Expresses alcoholic strenght as a percentage by volume of alcohol
(0%-100%)
• OIML measure stenght at 20ᵒC. where as GL measured at 15ᵒC.
25. Approximate Alcoholic Strenght
• Alcohol Free maximum 0.05%
• De- Alcoholised Maximum 0.5%
• Low Alcohol maximum 1.2%
• Cider 4-6% alcohol but special upto 8%
• Beer Light: 3-6%, Strong: 8-10%
• Table Wine 8-15%, usually 9-13%
• Sparkling Wine 10-13%
• Fortified Wine 16-22%
• Aromatised Wine 14-20%
• Vin doux Naturel 15-18%
• Spirit usually 37.5%-45%, some upto 57.5%
• Liqueurs 17-55%