Lecture 20 – Alcoholic Beverages Reading: Textbook, Chapter 14 In this lecture our attention will turn to plants that have been used to make beverages that are enjoyed widely in part because of their stimulating effect when consumed due to the presence of caffeine or similar compounds.

Alcohol Source = Yeast The ultimate source of alcohol for our beverages is a microorganism called yeast. This is a type of fungus that mostly reproduces asexually by the process of budding off new cells (fission). Yeast can grow in either aerobic (oxygen present) or anaerobic (oxygen not present) conditions, but it is only under anaerobic conditions that it produces alchohol as a waste product.

Alcohol Source = Yeast Source of ethanol: Saccharomyces species (yeasts) The ultimate source of alcohol for our beverages is a microorganism called yeast. This is a type of fungus that mostly reproduces asexually by the process of budding off new cells (fission). Yeast can grow in either aerobic (oxygen present) or anaerobic (oxygen not present) conditions, but it is only under anaerobic conditions that it produces alchohol as a waste product.

Alcohol Source = Yeast Source of ethanol: Saccharomyces species (yeasts) microorganism - fungus The ultimate source of alcohol for our beverages is a microorganism called yeast. This is a type of fungus that mostly reproduces asexually by the process of budding off new cells (fission). Yeast can grow in either aerobic (oxygen present) or anaerobic (oxygen not present) conditions, but it is only under anaerobic conditions that it produces alchohol as a waste product.

Alcohol Source = Yeast Source of ethanol: Saccharomyces species (yeasts) microorganism - fungus reproduce by fission (budding) The ultimate source of alcohol for our beverages is a microorganism called yeast. This is a type of fungus that mostly reproduces asexually by the process of budding off new cells (fission). Yeast can grow in either aerobic (oxygen present) or anaerobic (oxygen not present) conditions, but it is only under anaerobic conditions that it produces alchohol as a waste product.

Alcohol Source = Yeast Source of ethanol: Saccharomyces species (yeasts) microorganism - fungus reproduce by fission (budding) food = simple sugars only The ultimate source of alcohol for our beverages is a microorganism called yeast. This is a type of fungus that mostly reproduces asexually by the process of budding off new cells (fission). Yeast can grow in either aerobic (oxygen present) or anaerobic (oxygen not present) conditions, but it is only under anaerobic conditions that it produces alchohol as a waste product.

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 The ultimate source of alcohol for our beverages is a microorganism called yeast. This is a type of fungus that mostly reproduces asexually by the process of budding off new cells (fission). Yeast can grow in either aerobic (oxygen present) or anaerobic (oxygen not present) conditions, but it is only under anaerobic conditions that it produces alchohol as a waste product.

Alcohol - Chemistry Alcohol = organic compound with hydroxyl group (-OH) Isopropyl, or rubbing, alcohol, has 3 carbons arranged in a specific configuration. It has medical uses as a topical antiseptic, but is deadly poisonous if consumed internally.

Alcohol - Chemistry Alcohol = organic compound with hydroxyl group (-OH) Many different compounds that are alcohols Isopropyl, or rubbing, alcohol, has 3 carbons arranged in a specific configuration. It has medical uses as a topical antiseptic, but is deadly poisonous if consumed internally.

Alcohol - Chemistry Alcohol = organic compound with hydroxyl group (-OH) Many different compounds that are alcohols Beverage alcohol – specifically ethyl alcohol (ethanol) CH3-CH2OH Isopropyl, or rubbing, alcohol, has 3 carbons arranged in a specific configuration. It has medical uses as a topical antiseptic, but is deadly poisonous if consumed internally.

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, or rubbing, alcohol, has 3 carbons arranged in a specific configuration. It has medical uses as a topical antiseptic, but is deadly poisonous if consumed internally.

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 For a chemist, an alcohol is an entire class of organic compounds that is characterized by having the primary functional group be a hydroxyl (-OH) group. The “alcohol” for the average consumer is specifically ethyl alcohol, or ethanol, which has only 2 carbons. We will talk in detail about the chemical and physiological properties of this chemical compound. Another commonly encountered alcohol is methyl alcohol (methanol), which is also called wood alcohol because it can be made starting with woody tissues. Methanol is highly toxic to people, and in particular can cause blindness because of accumulations and further chemical reactions that occur in the eye. It is a useful solvent and found in many products, suching as cleaning and painting supplies. (As a note, organic chemists who also find methanol useful as a solvent are well aware that consumption of ethanol can help to detoxify methanol in the body, so a stop at the local pub after work has some justification). Isopropyl, or rubbing, alcohol, has 3 carbons arranged in a specific configuration. It has medical uses as a topical antiseptic, but is deadly poisonous if consumed internally. Both methanol and isopropanol are sometimes used to enrich supposed home brews, such as “white lightning”, and consumption of this type of product is not wise.

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 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 Gamma-aminobutyric acid (GABA) receptor  prevents firing of neurons that produce tenseness  calming effect 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 Gamma-aminobutyric acid (GABA) receptor  prevents firing of neurons that produce tenseness  calming effect Increases dopamine, endorphines  feeling of well-being 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 Gamma-aminobutyric acid (GABA) receptor  prevents firing of neurons that produce tenseness  calming effect Increases dopamine, endorphines  feeling of well-being 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: 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: 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 Acute toxicity – can cause death through depression of central brain stem See Fig. 14.2, p. 336

Alcohol – Negative Health Effects Acute toxicity – can cause death through depression of central brain stem Accidents through impaired thought and coordination – U.S. estimated 20,000 deaths/year See Fig. 14.2, p. 336

Alcohol – Negative Health Effects Acute toxicity – can cause death through depression of central brain stem Accidents through impaired thought and coordination – U.S. estimated 20,000 deaths/year 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 See Fig. 14.2, p. 336

Alcohol – Negative Health Effects Acute toxicity – can cause death through depression of central brain stem Accidents through impaired thought and coordination – U.S. estimated 20,000 deaths/year 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 Alcoholism – alcohol can be an addictive drug; may be a genetic basis. Prolonged use of alcohol  liver damage, permanent brain damage, severe malnutrition See Fig. 14.2, p. 336

Alcohol – Negative Health Effects Acute toxicity – can cause death through depression of central brain stem Accidents through impaired thought and coordination – U.S. estimated 20,000 deaths/year 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 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 See Fig. 14.2, p. 336

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 By definition, the starting material for beers is grain - this distinguishes these beverages from wines. The most commonly consumed beers in our country are based on barley. A problem in producing any beer is to convert the starches in the grain into sugars that can be metabolized by yeasts. In sake, this process utilizes another fungus and produces a more potent beverage. The traditional beer of native american groups in Mexico starts with corn to which saliva - with its enzymes that break down starch into sugar - is added by chewing.

Beer, Ale, Sake Beers – made from fermented grains Lager beers – bottom-fermenting yeasts By definition, the starting material for beers is grain - this distinguishes these beverages from wines. The most commonly consumed beers in our country are based on barley. A problem in producing any beer is to convert the starches in the grain into sugars that can be metabolized by yeasts. In sake, this process utilizes another fungus and produces a more potent beverage. The traditional beer of native american groups in Mexico starts with corn to which saliva - with its enzymes that break down starch into sugar - is added by chewing.

Beer, Ale, Sake Beers – made from fermented grains Lager beers – bottom-fermenting yeasts Ales, bitters - top-fermenting yeasts By definition, the starting material for beers is grain - this distinguishes these beverages from wines. The most commonly consumed beers in our country are based on barley. A problem in producing any beer is to convert the starches in the grain into sugars that can be metabolized by yeasts. In sake, this process utilizes another fungus and produces a more potent beverage. The traditional beer of native american groups in Mexico starts with corn to which saliva - with its enzymes that break down starch into sugar - is added by chewing.

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%) By definition, the starting material for beers is grain - this distinguishes these beverages from wines. The most commonly consumed beers in our country are based on barley. A problem in producing any beer is to convert the starches in the grain into sugars that can be metabolized by yeasts. In sake, this process utilizes another fungus and produces a more potent beverage. The traditional beer of native american groups in Mexico starts with corn to which saliva - with its enzymes that break down starch into sugar - is added by chewing.

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 By definition, the starting material for beers is grain - this distinguishes these beverages from wines. The most commonly consumed beers in our country are based on barley. A problem in producing any beer is to convert the starches in the grain into sugars that can be metabolized by yeasts. In sake, this process utilizes another fungus and produces a more potent beverage. The traditional beer of native american groups in Mexico starts with corn to which saliva - with its enzymes that break down starch into sugar - is added by chewing.

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) By definition, the starting material for beers is grain - this distinguishes these beverages from wines. The most commonly consumed beers in our country are based on barley. A problem in producing any beer is to convert the starches in the grain into sugars that can be metabolized by yeasts. In sake, this process utilizes another fungus and produces a more potent beverage. The traditional beer of native american groups in Mexico starts with corn to which saliva - with its enzymes that break down starch into sugar - is added by chewing.

History of Beer Ca 6000 yrs ago? Beer has been consumed for as long as written records have been kept.

History of Beer Ca 6000 yrs ago? Sumerians – used much of their grain to make beer Beer has been consumed for as long as written records have been kept.

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 Beer has been consumed for as long as written records have been kept.

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 Beer has been consumed for as long as written records have been kept.

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 Beer has been consumed for as long as written records have been kept.

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 has been consumed for as long as written records have been kept.

Beer Ingredients Barley Malt Barley – preferred because contains large amounts of enzymes that convert starches to sugars The process of malting involves a process that liberates the starch-converting enzymes that are naturally present in the barley grain. It also adds flavor compounds that are produced by the heating process.

Beer Ingredients Barley Malt Barley – preferred because contains large amounts of enzymes that convert starches to sugars Malting: causing the grain to sprout, then drying it The process of malting involves a process that liberates the starch-converting enzymes that are naturally present in the barley grain. It also adds flavor compounds that are produced by the heating process.

Beer Ingredients 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 The process of malting involves a process that liberates the starch-converting enzymes that are naturally present in the barley grain. It also adds flavor compounds that are produced by the heating process.

Beer Ingredients 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 The process of malting involves a process that liberates the starch-converting enzymes that are naturally present in the barley grain. It also adds flavor compounds that are produced by the heating process.

Beer Ingredients 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 The process of malting involves a process that liberates the starch-converting enzymes that are naturally present in the barley grain. It also adds flavor compounds that are produced by the heating process.

Beer Ingredients 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 The process of malting involves a process that liberates the starch-converting enzymes that are naturally present in the barley grain. It also adds flavor compounds that are produced by the heating process.

Beer Ingredients 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 Although beers can be flavored in a variety of ways, the use of hops became standard at a time when preservation of the brew was an important consideration.

Beer Ingredients 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 Yeast – Saccharomyces uuvuram (lager beers); S. cerevisiae (ale) Water – pH, mineral content – affect taste

Beer Brewing – Basic Steps Malting  Liberate enzymes (diastatic power) Mashing  Enzymes convert starch  sugar Drain liquid = wort Add hops (flavoring) Fermentation  “green beer” Aging (“lagering”) Pasteurization/filtering Re-addition of carbon dioxide 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