Thursday Lecture – Alcoholic Beverages

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Transcript Thursday Lecture – Alcoholic Beverages

Lecture 20 – Alcoholic Beverages
Reading: Textbook, Chapter 14
Alcohol Source = Yeast
Alcohol Source = Yeast
Source of ethanol: Saccharomyces species (yeasts)
Alcohol Source = Yeast
Source of ethanol: Saccharomyces species (yeasts)
- microorganism - fungus
Alcohol Source = Yeast
Source of ethanol: Saccharomyces species (yeasts)
- microorganism - fungus
- reproduce by fission (budding)
Alcohol Source = Yeast
Source of ethanol: Saccharomyces species (yeasts)
- microorganism - fungus
- reproduce by fission (budding)
- food = simple sugars only
Alcohol Source = Yeast
Source of ethanol: Saccharomyces species (yeasts)
- microorganism - fungus
- reproduce by fission (budding)
- food = simple sugars only
- anaerobic conditions 
degrade sugars to alcohol
Alcohol - Chemistry
Alcohol = organic compound with hydroxyl group (-OH)
Alcohol - Chemistry
Alcohol = organic compound with hydroxyl group (-OH)
Many different compounds that are alcohols
Alcohol - Chemistry
Alcohol = organic compound with hydroxyl group (-OH)
Many different compounds that are alcohols
Beverage alcohol – specifically ethyl alcohol (ethanol)
CH3-CH2OH
Alcohol - Chemistry
Alcohol = organic compound with hydroxyl group (-OH)
Many different compounds that are alcohols
Beverage alcohol – specifically ethyl alcohol (ethanol)
CH3-CH2OH
Other common alcohols:
Methyl alcohol, methanol (wood alcohol): CH3OH
Alcohol - Chemistry
Alcohol = organic compound with hydroxyl group (-OH)
Many different compounds that are alcohols
Beverage alcohol – specifically ethyl alcohol (ethanol)
CH3-CH2OH
Other common alcohols:
Methyl alcohol, methanol (wood alcohol): CH3OH
Isopropyl alcohol, isopropanol (rubbing alcohol): CH3CH3CHOH
Alcohol – As a Drug
Effects of alcohol on human physiology
-
complex set of responses
Alcohol – As a Drug
Effects of alcohol on human physiology
-
complex set of responses
-
nervous system depressant
Alcohol – As a Drug
Effects of alcohol on human physiology
-
complex set of responses
-
nervous system depressant
-
interferes with specific neuroreceptors
Alcohol – As a Drug
Effects of alcohol on human physiology
-
complex set of responses
-
nervous system depressant
-
interferes with specific neuroreceptors
1. Gamma-aminobutyric acid (GABA) receptor  prevents firing
of neurons that produce tenseness  calming effect
Alcohol – As a Drug
Effects of alcohol on human physiology
-
complex set of responses
-
nervous system depressant
-
interferes with specific neuroreceptors
1. Gamma-aminobutyric acid (GABA) receptor  prevents firing
of neurons that produce tenseness  calming effect
2. Increases dopamine, endorphines  feeling of well-being
Alcohol – As a Drug
Effects of alcohol on human physiology
-
complex set of responses
-
nervous system depressant
-
interferes with specific neuroreceptors
1. Gamma-aminobutyric acid (GABA) receptor  prevents firing
of neurons that produce tenseness  calming effect
2. Increases dopamine, endorphines  feeling of well-being
3. Interference with glutamate receptors  disrupts signals that
control muscles  feeling of relaxation + lethargy + inability
to control muscles  can slow heart and breathing rates and
cause death
Alcohol – As a Drug
Effects of alcohol on human physiology
-
complex set of responses
-
nervous system depressant
-
interferes with specific neuroreceptors
1. Gamma-aminobutyric acid (GABA) receptor  prevents firing
of neurons that produce tenseness  calming effect
2. Increases dopamine, endorphines  feeling of well-being
3. Interference with glutamate receptors  disrupts signals that
control muscles  feeling of relaxation + lethargy + inability
to control muscles  can slow heart and breathing rates and
cause death
- NMDA, type of glutamate receptor involved with memory 
interferes with short term memory formation
Alcohol – Physiology
Absorption – 20% in stomach; 80% in intestine
Alcohol – Physiology
Absorption – 20% in stomach; 80% in intestine
-
absorption through stomach is slower, if food is present, alcohol
moves more slowly into intestine, and some is also oxidized
Alcohol – Physiology
Absorption – 20% in stomach; 80% in intestine
-
absorption through stomach is slower, if food is present, alcohol
moves more slowly into intestine, and some is also oxidized
Bloodstream – BAC = Blood Alcohol Concentration
 Circulated to all parts of body; broken down only in liver
Alcohol – Physiology
Absorption – 20% in stomach; 80% in intestine
-
absorption through stomach is slower, if food is present, alcohol
moves more slowly into intestine, and some is also oxidized
Bloodstream – BAC = Blood Alcohol Concentration
 Circulated to all parts of body; broken down only in liver
>Water content  greater absorption
Alcohol – Physiology
Absorption – 20% in stomach; 80% in intestine
-
absorption through stomach is slower, if food is present, alcohol
moves more slowly into intestine, and some is also oxidized
Bloodstream – BAC = Blood Alcohol Concentration
 Circulated to all parts of body; broken down only in liver
>Water content  greater absorption
> Fat Content  less absorption
Alcohol – Physiology
Absorption – 20% in stomach; 80% in intestine
-
absorption through stomach is slower, if food is present, alcohol
moves more slowly into intestine, and some is also oxidized
Bloodstream – BAC = Blood Alcohol Concentration
 Circulated to all parts of body; broken down only in liver
>Water content  greater absorption
> Fat Content  less absorption
Liver – enzyme, alcohol dehydrogenase, breaks down ethanol
Alcohol – Physiology
Absorption – 20% in stomach; 80% in intestine
-
absorption through stomach is slower, if food is present, alcohol
moves more slowly into intestine, and some is also oxidized
Bloodstream – BAC = Blood Alcohol Concentration
 Circulated to all parts of body; broken down only in liver
>Water content  greater absorption
> Fat Content  less absorption
Liver – enzyme, alcohol dehydrogenase, breaks down ethanol
NOTE: Women less tolerant to alcohol than men:
1. Smaller body size; 2. More rapid emptying of stomach; 3.
Higher proportion of fat in body tissues
Alcohol – Physiology
Absorption – 20% in stomach; 80% in intestine
-
absorption through stomach is slower, if food is present, alcohol
moves more slowly into intestine, and some is also oxidized
Bloodstream – BAC = Blood Alcohol Concentration
 Circulated to all parts of body; broken down only in liver
>Water content  greater absorption
> Fat Content  less absorb.
Liver – enzyme, alcohol dehydrogenase, breaks down ethanol
NOTE: Women less tolerant to alcohol than men:
1. Smaller body size; 2. More rapid emptying of stomach; 3.
Higher proportion of fat in body tissues
Carbonation:  alcohol enters intestines more rapidly
Alcohol – Positive Health Effects
Alcohol – Positive Health Effects
Low to moderate doses:
- no evidence of persistent, harmful effects
Alcohol – Positive Health Effects
Low to moderate doses:
- no evidence of persistent, harmful effects
- epidemiology (what is this?):
2 drinks/day  lowers risk of heart disease (mechanism:
raises level of high-density lipoproteins in blood
Alcohol – Positive Health Effects
Low to moderate doses:
- no evidence of persistent, harmful effects
- epidemiology (what is this?):
2 drinks/day  lowers risk of heart disease (mechanism:
raises level of high-density lipoproteins in blood
- inhibition releaser
low levels  promotes laughter, playful behavior,
socialization
Alcohol – Positive Health Effects
Low to moderate doses:
- no evidence of persistent, harmful effects
- epidemiology (what is this?):
2 drinks/day  lowers risk of heart disease (mechanism:
raises level of high-density lipoproteins in blood
- inhibition releaser
low levels  promotes laughter, playful behavior,
socialization
Recent research – results that indicate in women over the age of 60,
regular low consumption of alcohol helps with memory retention
Alcohol – Negative Health Effects
1. Acute toxicity – can cause death through depression of central
brain stem
See Fig. 14.2, p. 336
Alcohol – Negative Health Effects
1. Acute toxicity – can cause death through depression of central
brain stem
See Fig. 14.2, p. 336
2. Accidents through impaired thought and coordination – U.S.
estimated 20,000 deaths/year
Alcohol – Negative Health Effects
1. Acute toxicity – can cause death through depression of central
brain stem
See Fig. 14.2, p. 336
2. Accidents through impaired thought and coordination – U.S.
estimated 20,000 deaths/year
3. Fetal Alcohol Syndrome – correlated with drinking during
pregnancy, leads to fetal abnormalities (reduced brain size,
small eyeballs, malformations of lips and jaw). Effects can be
persistent
Alcohol – Negative Health Effects
1. Acute toxicity – can cause death through depression of central
brain stem
See Fig. 14.2, p. 336
2. Accidents through impaired thought and coordination – U.S.
estimated 20,000 deaths/year
3. Fetal Alcohol Syndrome – correlated with drinking during
pregnancy, leads to fetal abnormalities (reduced brain size,
small eyeballs, malformations of lips and jaw). Effects can be
persistent
4. Alcoholism – alcohol can be an addictive drug; may be a
genetic basis. Prolonged use of alcohol  liver damage,
permanent brain damage, severe malnutrition
Alcohol – Negative Health Effects
1. Acute toxicity – can cause death through depression of central
brain stem
See Fig. 14.2, p. 336
2. Accidents through impaired thought and coordination – U.S.
estimated 20,000 deaths/year
3. Fetal Alcohol Syndrome – correlated with drinking during
pregnancy, leads to fetal abnormalities (reduced brain size,
small eyeballs, malformations of lips and jaw). Effects can be
persistent
4. Alcoholism – alcohol can be an addictive drug; may be a
genetic basis. Prolonged use of alcohol  liver damage,
permanent brain damage, severe malnutrition
NOTE: alcohol + other drugs  dangerous interactions can occur
Fermentation
Fermentation
Notes:
- requires simple sugar, or disaccharides, as input (starch not used)
Fermentation
Notes:
- requires simple sugar, or disaccharides, as input (starch not used)
- requires anaerobic conditions
Fermentation
Notes:
- requires simple sugar, or disaccharides, as input (starch not used)
- requires anaerobic conditions
- step-wise set of reactions (not shown here – see Fig. 14.3, p. 336)
Fermentation
Notes:
- requires simple sugar, or disaccharides, as input (starch not used)
- requires anaerobic conditions
- step-wise set of reactions (not shown here – see Fig. 14.3, p. 336)
- produces ethanol and carbon dioxide (gas)
Fermentation
Notes:
- requires simple sugar, or disaccharides, as input (starch not used)
- requires anaerobic conditions
- step-wise set of reactions (not shown here – see Fig. 14.3, p. 336)
- produces ethanol and carbon dioxide (gas)
- utilizes only a fraction of the energy available in the sugar
Types of Alcoholic Beverages
Wine: fermented fruit juice
Types of Alcoholic Beverages
Wine: fermented fruit juice
Mead: fermented honey
Types of Alcoholic Beverages
Wine: fermented fruit juice
Mead: fermented honey
Beer: fermented grain
Types of Alcoholic Beverages
Wine: fermented fruit juice
Mead: fermented honey
Beer: fermented grain
Other beverages require either distillation or addition of
alcohol from distillation
Beer, Ale, Sake
Beers – made from fermented grains
Beer, Ale, Sake
Beers – made from fermented grains
Lager beers – bottom-fermenting yeasts
Beer, Ale, Sake
Beers – made from fermented grains
Lager beers – bottom-fermenting yeasts
Ales, bitters - top-fermenting yeasts
Beer, Ale, Sake
Beers – made from fermented grains
Lager beers – bottom-fermenting yeasts
Ales, bitters - top-fermenting yeasts
Sake: rice “wine” – made from rice, Aspergillus fungus 
liberates sugar  higher concentration of alcohol (18%)
Beer, Ale, Sake
Beers – made from fermented grains
Lager beers – bottom-fermenting yeasts
Ales, bitters - top-fermenting yeasts
Sake: rice “wine” – made from rice, Aspergillus fungus 
liberates sugar  higher concentration of alcohol (18%)
Chicha: starts with chewed kernels of corn
Beer, Ale, Sake
Beers – made from fermented grains
Lager beers – bottom-fermenting yeasts
Ales, bitters - top-fermenting yeasts
Sake: rice “wine” – made from rice, Aspergillus fungus 
liberates sugar  higher concentration of alcohol (18%)
Chicha: starts with chewed kernels of corn
Pulque: uses sap of Agave (compare to tequila, below)
History of Beer
Ca 6000 yrs ago?
History of Beer
Ca 6000 yrs ago?
Sumerians – used much of their grain to make beer
History of Beer
Ca 6000 yrs ago?
Sumerians – used much of their grain to make beer
Early brewing – linked to bread making
- Barley breads – made from sprouted grain  dough was
logical place for fermentation to occur
History of Beer
Ca 6000 yrs ago?
Sumerians – used much of their grain to make beer
Early brewing – linked to bread making
- Barley breads – made from sprouted grain  dough was
logical place for fermentation to occur
- Source of microbes not controlled  not always
Saccharomyces, so batches could vary greatly
History of Beer
Ca 6000 yrs ago?
Sumerians – used much of their grain to make beer
Early brewing – linked to bread making
- Barley breads – made from sprouted grain  dough was
logical place for fermentation to occur
- Source of microbes not controlled  not always
Saccharomyces, so batches could vary greatly
Relatively Recent – Standardization of methods to produce beer
of consistently uniform quality
History of Beer
Ca 6000 yrs ago?
Sumerians – used much of their grain to make beer
Early brewing – linked to bread making
- Barley breads – made from sprouted grain  dough was
logical place for fermentation to occur
- Source of microbes not controlled  not always
Saccharomyces, so batches could vary greatly
Relatively Recent – Standardization of methods to produce beer
of consistently uniform quality
NOTE: beers made the traditional way can be highly nutritious
– “liquid bread” – have significant proteins, vitamins
Beer Ingredients
1. Barley Malt
Barley – preferred because contains large amounts of
enzymes that convert starches to sugars
Beer Ingredients
1. Barley Malt
Barley – preferred because contains large amounts of
enzymes that convert starches to sugars
Malting: causing the grain to sprout, then drying it
Beer Ingredients
1. Barley Malt
Barley – preferred because contains large amounts of
enzymes that convert starches to sugars
Malting: causing the grain to sprout, then drying it
-
grain is washed 8-10 hrs  absorbs water
Beer Ingredients
1. Barley Malt
Barley – preferred because contains large amounts of
enzymes that convert starches to sugars
Malting: causing the grain to sprout, then drying it
-
grain is washed 8-10 hrs  absorbs water
-
grain sits in water ca 40 hrs
Beer Ingredients
1. Barley Malt
Barley – preferred because contains large amounts of
enzymes that convert starches to sugars
Malting: causing the grain to sprout, then drying it
-
grain is washed 8-10 hrs  absorbs water
-
grain sits in water ca 40 hrs
-
water is drained; grain sits controlled room 6 days 
production of amylases, enzymes that break down
starch; other processes  reduce cloudiness
Beer Ingredients
1. Barley Malt
Barley – preferred because contains large amounts of
enzymes that convert starches to sugars
Malting: causing the grain to sprout, then drying it
-
grain is washed 8-10 hrs  absorbs water
-
grain sits in water ca 40 hrs
-
water is drained; grain sits controlled room 6 days 
production of amylases, enzymes that break down
starch; other processes  reduce cloudiness
-
germination process stopped by heating
Beer Ingredients
2. Hops – Humulus lupulus
(Cannabaceae)
Dioecious vine – female flowering
structures utilized
- provides flavor associated with
beer
- adds enzymes  coagulate
proteins, reduce cloudiness
-
appears to have antibacterial
activity
NOTE: other plants have been
used to flavor beers
Beer Ingredients
3. Adjuncts
Unmalted grains – barley, rice, wheat; corn syrup; potatoes –
contain starches that can be converted to sugar (economic
consideration – less expensive than malted barley)
 Light-flavored beer, preferred in U.S.
Beer produced this way will also have fewer proteins
4. Yeast – Saccharomyces uuvuram (lager beers); S. cerevisiae
(ale)
5. Water – pH, mineral content – affect taste
Beer Brewing – Basic Steps
1. Malting  Liberate enzymes (diastatic power)
2. Mashing  Enzymes convert starch  sugar
3. Drain liquid = wort
4. Add hops (flavoring)
5. Fermentation  “green beer”
6. Aging (“lagering”)
7. Pasteurization/filtering
8. Re-addition of carbon dioxide
9. Bottling
Distillation
Water – boils at 100 C (212 F)
Ethanol – boils at 78.5 C (173.3 F)
Distillation
Water – boils at 100 C (212 F)
Ethanol – boils at 78.5 C (173.3 F)
Mixture is heated; ethanol gas is
driven off at lower temperature;
gathered in condenser – note, various
devices added to minimize water
vapor from escaping
Distillation
Water – boils at 100 C (212 F)
Ethanol – boils at 78.5 C (173.3 F)
Mixture is heated; ethanol gas is
driven off at lower temperature;
gathered in condenser – note, various
devices added to minimize water
vapor from escaping
Note: owning a still is illegal in
the U.S. and Canada!
Distilled Alcoholic Beverages Whiskeys
Whiskey: made from malted barley, or malted barley + other grain
- proof = twice concentration of alcohol (90 proof = 45% alcohol)
Scotch: made from barley malt; aged in charred casks
Bourbon: from Bourbon Co., Kentucky – 51+% corn
Tennessee sour mash: similar to bourbon; filtered through charcoal
Rye: 51% rye grain
Straight whiskey: <80 proof; aged 2+ years in new charred barrels
Other Distilled Beverages
Gin, Vodka – distilled to high percentage of alcohol
Gin: flavored with juniper “berries” (fleshy cones)
Vodka: malt, grains, potatoes (variously mixed)
Rum: distilled from molasses or sugar cane juice
Tequila, Mescal: Mexico, produced from Agave