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10 Caffeine, Alcohol, and Sweeteners - HANS T. BECK
174 • The Cultural History of Plants
Spreading coffee beans in Brazil, ca.1940. Library of Congress, Prints & Photographs Division, FSA-OWI Collection, LC-USF344-091285-B DLC.
related to one another and are all very weak alkaloids. Although some chemists don’t like to ascribe
them to the alkaloid class, they are by deﬁnition alkaloids, and in physiological action they are addictive. More than sixty plant species throughout the world contain caffeine, ranging between such taxonomically distant plant families as Liliaceae to Asteraceae. Although the Liliaceae and Asteraceae are
widespread, the plant families Sterculiaceae, Rubiaceae, Aquifoliaceae, Theaceae, and Sapindaceae
lead the list of taxa from which the most culturally signiﬁcant stimulant beverages are derived.
The physiological reactions of human bodies to the three methylated xanthines are similar.
The xanthines competitively inhibit the enzyme phophodiesterase, which results in an increase of
one the body’s basic energy units, cyclic adenosine monophosphate (cAMP), with a subsequent
release of endogenous epinephrine in the blood. This results in the direct relaxation of the
smooth muscles of the lungs’ bronchi and pulmonary vessels, leading to stimulation of the central nervous system and induction of diuresis, coupled with an increase digestive tract activity
and gastric acid secretion, an inhibition of uterine contractions, and topped off with a weak positive
TABLE 10.1 Substituting a Methyl Group at One or More Positions R1,
R3, R7 of the Xanthine Ring Produces Mild Stimulants
1, 3, 7-trimethylxanthine
Caffeine, Alcohol, and Sweeteners • 175
chronotropic and isotropic effect on the heart. In other words, you feel energized, breathing is
easier, and you can’t help but to run more often to the toilet. After consumption of coffee, tea, or
cocoa, demethylated products appear in the blood within three hours, but complete clearance of
caffeine and its derivates takes as much as a week. Caffeine has a toxicity rating of 4 on a scale of 10,
and symptoms of caffeine poisoning include tachycardia (rapid heart rate), excitement, convulsions, restlessness, tremors, frequent urination, tinnitus, nausea, and vomiting. Six percent of all
Americans suffer from chronic caffeine intoxication severe enough to require professional medical treatment.
However, concerns about addiction to caffeine, alcohol, and sugar have not dominated most of
man’s cultural history. Indeed, we shall learn of a great range of plants serving mankind’s desire for
beverages and sweeteners. The positive properties of beverages derived from these plants reﬂect a
long tradition of culinary customs, brewing heritage, and technological development. Beverage and
sweetener plants have played a central role in the cultures of most peoples, past and present.
Tea Camellia sinensis
Camellia has eighty-two species, yet only one has a dominant role in various cultures and has risen
to dominate worldwide beverage markets. Camellia sinensis is an evergreen shrub or tree, kept artiﬁcially small by the harvesting and plucking of top, terminal leaf shoots. These leaves, variously
processed, contain caffeine (1 to 5 percent) and traces of theophylline, theobromine, and other xanthine alkaloids; however, it is the essential oils that are responsible for the ﬂavors. Polyphenols (5 to
27 percent) are responsible for the dark brown tannin color.
The plant’s origin is in China, but its geographic distribution today reﬂects its cultivation in China
and Japan and in countries that were previously colonies of the British Empire, such as Sri Lanka,
India, Kenya, and the Carolinas in the United States, as well as Uganda, Turkey, and Indonesia. The
plant can grow as far north as 43°N in the Caucasus mountains and as far south as 28°S in Argentina.
There are two varieties cultivated in different environments: C. sinensis var. sinensis is a dwarf tree
with small leaves that is grown in the highlands, whereas C. s. var. assamica is a larger tree with larger
leaves that is grown in the lowlands. Tea plants are cross-pollinated, and they are propagated by seeds
Tea pickers in the Himalayas, India, between 1890 and 1923. Library of Congress, Prints & Photographs
176 • The Cultural History of Plants
and cuttings. The harvesting of tea is very labor-intensive: in the lowlands, every 7 days; in the highlands,
every 14 days. A mature plant yields about 2 lb green leaf per year, or about 0.5 lb dry weight.
One acre yields 1000 lb per annum, and 2 billion lb of black tea are harvested each year.
Three main production processes can occur with the plucked leaves, each of which produces a
well-known type of tea; however, the general public tends not to associate the process with the
product. Green tea is made from shoots that are steamed (Japanese) or parched (Chinese), rolled, and
dried. The heat halts the oxidative degradation process that turns leaves dark-colored, leaving them
green and light tasting. While traditionally consumed mostly in Asia, green tea is earning a global reputation for its healthful properties. Pouchong or Oolong tea is made from shoots that are withered in
the sun, stored indoors, and pan-dried at a succession of temperatures. This produces the typical curly
leaves of this “half-fermented” tea. Oolong tea, typically encountered in Chinese restaurants in Europe
and North America, has a relatively minor level of consumption worldwide compared to black tea.
Black tea is made from fresh shoots that are ﬁrst rolled and then crushed; thereafter, the mass is
allowed to ferment, which allows oxidation of phenolic compounds, giving the dark, black color. The
application of heat ends the fermentation, and the leaves are pan dried. Although India and Sri Lanka
produce most of the black tea, it is consumed throughout world. However, there are rather striking
regional differences in consumption. These differences are related directly to the story of coffee.
See: Age of Industrialization and Agro-industry pp. 369–71
Coffee Coffea spp.
Within the large, alkaloid-rich, tropical family Rubiaceae, Coffea, with approximately 90 species, shares
fame with the notable medicinal and psychoactive genera Cephaelis (formally Cephaelis) (from which is
derived ipecacuanha, used as an emetic and expectorant), Cinchona (quinine), Pausinystalia (yohimbine, used in a prescription drug to treat male erectile dysfunction), and Uncaria (cat’s claw, traditionally used in South American folk medicine, and shown to be an immunostimulant). Three economically
important species of the Coffea family are the major source of stimulant beverages: arabica coffee, C.
arabica L.; robusta coffee, C. canephora (C. robusta); and liberica coffee, C. liberica. There is a large discrepancy in relative importance of the three coffee species in international commerce: C. arabica, with
75.5 percent of the market, is mostly cultivated in tropical America; C. canephora, with 24 percent, is
produced mostly in Africa; and C. liberica, with 0.5 percent, has mostly a small regional market.
Originating in Ethiopian upland forests, these small understory trees of tropical climates produce a ﬂeshy red fruit (technically a drupe, or stone fruit) that has been called “green gold.” Coffee
is best cultivated in equatorial latitudes, and its current geographic distribution reﬂects a colonial
history. Coffee ﬁrst spread to India and Ceylon in 16th and 17th centuries, and thereafter spread to
the West Indies and South America.
The harvesting of coffee is dependent on the ﬂowering ﬂushes that occur three to four times per
year. Hand-picked harvesting is necessary due to the staggered timing of fruit maturation. The icon
of Colombian coffee advertisements—Juan Valdez hand-picking every coffee bean—is not just a traditional rural farmer carrying on some quaint tradition; the biological reality of coffee reproduction
has not allowed for mechanical harvesting. Interestingly, the primary coffee production is outside of
Coffea’s home range of tropical Africa: Brazil has half of the world market, and Colombia is another
large producer. Other smaller or specialty production centers exist in Costa Rica, Mexico, Guatemala,
El Salvador, the Antilles, Hawaii, Angola, Tanzania, Uganda, Kenya, and Ivory Coast.
At this point, we must consider coffee leaf rust and why the British drink tea. Coffea arabica is
susceptible to a serious fungal disease—coffee leaf rust (Hemileia vastatrix)—that is native to Ethiopia.
This disease spread to Ceylon, but neglect of treatment caused an epidemic in colonial coffee plantations, and the industry collapsed. The British replanted with tea, and to this day, Ceylon teas are
Caffeine, Alcohol, and Sweeteners • 177
TABLE 10.2 Tea and Coffee Consumption Compared
Consumption Per Capita
most popular in Britain. We see this reﬂected in consumption per capita statistics (see Table 10.2).
Coffee leaf rust is now present in Brazil, and there is concern over the historical fact of coffee’s very
small genetic base in South America. Only six trees were originators of the massive market. The fungus is being controlled with fungicides but more importantly by hybridizing arabica stock (C. arabica)
with robusta stock (C. canephora); the resulting hybrids are more resistant to rust.
The coffee “bean” is a really a seed, and there are two seeds per fruit. In order to extract those
seeds, two types of processing have been developed—a traditional dry process and an industrial wet
process. The local, simple dry process involves spreading the fruits in sun and removing dried husk
by hand processing. The more common industrial wet process soaks the fruits in water, where the
“bad” ones ﬂoat and the “good” ones sink. The good ones are taken to a depulping machine, where
the fruits are gently macerated; afterwards, the mass is fermented, followed by a second rinse. The
green seeds are then dried and stored, to await sale to coffee houses and roasters. The roasting of
green beans caramelizes the sugars that give the characteristic ﬂavor. Two notable adulterants or
substitutes for coffee are made from the ground taproots of chicory (Cichorium intybus, Asteraceae)
and dandelion (Taraxacum ofﬁcinale, Asteraceae).
The chemical composition of coffee varies remarkably between species and with processing.
Green coffee has 0.6 to 3.2 percent caffeine, usually in the range of 1.5 to 2.5 percent, whereas
roasted coffee has slightly less caffeine than green: C. arabica has 1.5 percent caffeine; C. canephora,
2.7 percent caffeine.
Cacao, Cocoa, Chocolate Theobroma cacao
Theobroma cacao, one of 22 species, has been cultivated since antiquity and has complex subspeciﬁc
relationships. Several subspecies have been recognized, with a great number of cultivars developed
from them. The two main subspecies are Criollo, T. cacao ssp. cacao f. cacao, and Amazon Forastero,
T. cacao ssp. sphaerocarpum. A hybrid Criollo × Amazon Forastero is called Trinitario. The Criollo
Cacao seeds drying in Chachi canoe, Ecuador. Photo by Hans Beck.
178 • The Cultural History of Plants
subspecies is further divided with varieties Alligator cocoa, T. cacao ssp. cacao f. pentagonum, and
Porcelain Java Criollo, T. cacao ssp. cacao f. leiocarpum.
The earliest evidence of chocolate consumption is based on cacao residue in Mayan drinking
vessels dated at about 480 AD. However, scientists believe the pulp was eaten fresh or blended into a
beverage well before the roasting process was developed. Carved words and pictures on special pots
uncovered in archeological sites suggest that they were used to produce chocolate products for the
Mayan nobility. The Aztecs consumed a cold beverage made by combining corn, cacao seeds, water,
chilies, and other spices. It was believed to be an aphrodisiac. Spanish colonists in Central and
South America eventually reﬁned this bitter beverage by leaving out the chilies, adding sugar, anise,
and cinnamon, heating it to improve the texture, and serving it warm. As the demand for chocolate
products increased after European colonization, the chocolate tree was cultivated on large plantations. In Europe, only wealthy people were able to enjoy the early chocolate products because the
cacao seeds had to be imported. Evidence indicates that cacao seeds were used as currency in the
Yucatan until 1850 and were still considered valuable until about 1923.
Truly a gift from the gods, these small trees produce a leathery, American football/rugby ballshaped fruit (drupe), within which are found seeds covered by sweet, delicious, marshmallow-like
arils (the thick ﬂeshy envelope around the seed). However, it is the seeds that are the source of the
international commodity. While originally from neotropical ﬂooded rainforests, cacao’s primary
producers are now Ghana (30 percent), Nigeria (15 percent), and Brazil (20 percent). Interestingly,
the primary consumers are the United States (25 percent), Germany (13 percent), the United Kingdom (10 percent), and the Netherlands (9 percent).
Flowering is cauliﬂorous; that is, ﬂowers are borne on the trunk and stems. The small, delicate,
white ﬂowers are pollinated by midges, with a typical success rate of 1 in 500 ﬂowers producing a
large drupe. The fruits are harvested at the end of the rainy season, yielding 200 to 2000 lb/acre.
Cacao harvesting involves collecting fruits by hand, shelling, seed washing to remove the aril, fermenting, and drying; the dried seeds at this stage are called raw cacao. For factory processing,
seeds are roasted to facilitate seed-coat removal and hydraulically shattered into nibs, then
ground under pressure and heat. This produces a thick dark paste called “chocolate liquor”—the
base for all cocoa products. If the liquor is cooled and hardened, the result is “baking chocolate.”
If the liquor is subjected again to high pressure, an amber liquid called “cocoa butter” is extruded,
and the remaining chocolate press cake is ground to “cocoa powder” (the basis for powdered
cocoa beverages). If the cocoa butter is blended with more chocolate liquor, the mixture is on its
way to becoming chocolate candy: bittersweet, semisweet, and milk chocolate; white chocolate is
mostly cocoa butter. Chocolate is a stimulant, containing theobromine (0.5 to 2.7 percent) and
caffeine (0.25 to 1.7 percent).
Carob Ceratonia siliqua
Carob bean is the fruit of an evergreen long-lived tree with hard woody leaves, which naturally
grows on barren, rocky, and dry regions of the Mediterranean basin. It is said that the “locusts”
that John the Baptist lived on in the wilderness were carob pods, as “locust bean” is another name
for carob bean pods; the carob tree is thus sometimes called St. John’s bread. Archeobotanical
discoveries in the Middle East show that carob existed in the Eastern Mediterranean basin long
before the start of agriculture. Early literary sources indicate that its domestication took place
relatively late (only in Roman times). The probable reason for this late date is that the carob does
not lend itself to simple vegetative propagation, and its cultivation had to wait until the introduction of scion grafting into the Mediterranean basin. Carob cultivation reached its peak in this
region in early Islamic times.
Caffeine, Alcohol, and Sweeteners • 179
The carob pod is dried, roasted, and, after the seeds are removed, ground to be consumed as a
beverage, as a coffee substitute. The ground pods also compete with cocoa powder, and can be
made into bars of carob “chocolate.” Whole carob pods, with their thick, sweet pulp, were sold as
“sweets” to be chewed raw in the United Kingdom during World War II when sweets were rationed,
and are also used as animal fodder in the Middle East. As carob does not contain either caffeine or
theobromine, it is marketed as a healthy substitute for coffee and chocolate.
Cola, Kola Cola spp.
Typically cultivated in tropical West Africa as large trees, there are approximately 125 species of
Cola known, but only two have entered signiﬁcantly into U.S. and European markets for their
beverage use. The removal of the ﬂeshy red seed coat exposes the embryo, or “kola nut,” which is
the caffeine-containing seed that is chewed or used as a caffeine source and ﬂavoring for cola
drinks. The history of the slave trade triangle (Africa, New World, Europe) plays into this story of
the beverage: slaves brought Cola nitida (originally distributed from Sierra Leone to Cameroon)
to the Caribbean, and C. acuminata (abata cola, distributed from Benin to Angola) to Brazil.
Other species such as C. anomala and C. verticillata are also grown in West Africa and are locally
Cola propagation is by seeds or cuttings, full seed production begins at 20 years, and trees will
produce well until 70 years. Typical yields are about 500 pounds of kola nuts/acre. Cola nitida is
cultivated extensively in the tropics and is the major source of commercial cola nuts. The primary
producers are Nigeria (100,000 tons/year) and Ivory Coast (30,000 tons/year). The main products
and use of cola is as a ﬂavoring and stimulant source for carbonated soft drinks and as diet/energy
formulas in tablet form. With just trace amounts of theobromine, cola has a good amount of caffeine (1.0 to 2.5 percent), and can be found in many soft drinks such as Coca-Cola and Pepsi-Cola,
although synthetic ﬂavorings are now supplanting this use.
See: Nuts, Seeds, and Pulses p. 137; Plants as Medicine pp. 208–9
Guaraná Paullinia cupana
The beverage with the highest natural caffeine content in the world is made from the roasted seeds
of guaraná, a woody climber of tropical Amazonia. The fruits are orange to red capsules containing
black seeds partially covered by white arils. The contrast of the colors in the split-open fruit gives
them the appearance of eyeballs. Indeed, the origin myth behind guaraná’s domestication is attributed to the Sateré-Maué Indians of Brazil, the ﬁrst consumers of the guaraná beverage, who tell of a
malevolent god who lures into the jungle and kills a beloved village child out of jealousy. The village
ﬁnds the dead child lying in the forest , and a benevolent god consoles them in their grief with a gift
in the form of guaraná. The good god plucks out the left eye of the child and plants it in the forest,
where it becomes the wild variety of guaraná; the right eye is planted in the village garden, where it
sprouts and produces fruits resembling the eye of the child, forever after a pleasant reminder of
their favorite but lost child. The Sateré-Maué continue to cultivate guaraná orchards, harvest the
large sprays of fruit, extract the seeds, roast them, and form them into smoke-cured sticks (bastao).
In preparing traditional guaraná beverage, these sticks are rasped with the hyoid bone of the
pirarucu ﬁsh, producing a powder that is mixed with water and consumed fresh.
The fame of the caffeine-rich seeds spread throughout the Amazon, and the global demand for
guaraná now is primarily supplied by industrial plantation cultivation, where the plants are maintained with a shrub-like habit. The main production centers are in Maués and Manaus, Brazil.
Active research and breeding programs seek, by seed or asexual propagation by stem cuttings, to
180 • The Cultural History of Plants
develop and maintain high seed-yielding cultivars with disease resistance. Seed harvest begins after
the third year, and continues for up to 80 years, with yields of approximately 125 kg per harvest.
Fruit maturation occurs in October–November, and the harvest coincides with the guaraná festival
in Maués. The small agricultural town sees its population swell with visitors from throughout
Amazonia during one week of festivities, including parades, pageants, folkloric theatre, music, agricultural extension service, and, of course, consumption of guaraná beverages.
The varied uses and products include local hot or cold beverages, carbonated soft drinks, and
energy/diet pills. Guaraná is claimed to be the national drink of Brazil, where more than 17 million
bottles per day are consumed. While the limited Amazonian production restricts international
exports, guaraná is showing up in international markets in tea powder, herbal mixes, and expensive,
specially-crafted, high-energy/high-caffeine drinks. Its use in such liquid products is due to its high
levels of caffeine (4 to 7.5 percent) and traces of theobromine and theophylline.
Yerba maté, Brazilian tea, Paraguay tea Ilex paraguariensis
The stimulant beverage yerba maté is derived from the leaves of medium-sized trees grown in subtropical South American plantations. Primary production is centered in southern Brazil, Paraguay,
and Argentina. The harvest involves clipping leaves, drying them, and grinding the dried leaves in
order to produce a powder. Maté production is mostly regional, and international exports are limited, restricted to herbal tea mixes like “Morning Thunder.” However, maté is the national drink of
Paraguay, Uruguay, and Argentina, where it enjoys a social and cultural status rivaling that of tea
and coffee in its depth of custom. The dried leaves are sold in bulk under many brand names, packaged typically in half-kilogram bags.
Aﬁcionados of this beverage have their brand preferences, beverage recipes, and special utensils.
The paraphernalia needed to consume hot infusions of yerba maté are a maté (a traditional cup
made from a gourd or horn), a bombilla (a spoon-shaped straw with built-in strainer), a hot water
bottle or pot, and a pouch to carry one’s yerba maté supply and utensils. The matéis ﬁlled with
yerba maté and then covered with hot water. The liquid is sucked through the bombilla’s strainer,
leaving behind the leaves in the cup, which is ﬁlled multiple times with water. The consumption of
the beverage, with its caffeine level of 2 to 2.5 percent, is a social affair, with groups of people, college students especially, often spending leisurely hours in conversation, sharing matés and passing
the hot water containers. The utensils are often decorated, sometimes highly ﬁligreed with silver,
gold, and jewels.
Alcoholic Beverages and Beverage Flavorings
Absinthe, Wormwood Artemisia absinthium
Known since 77 AD in the time of Pliny, this aromatic herb was often used for its vermifugic (deworming) and stimulant properties, the latter due to a psychoactive ketone, thujone. The genuine
absinthe beverage was an expensive liqueur prepared by distilling alcohol in which the leaves of
Artemisia absinthium were soaked. The drink is especially associated with the French distillery
Pernod Fils and was popular with the Impressionist painters. A huge demand for the beverage
among the wealthy and the intelligentsia of western Europe in the late 19th century led to a craze
for absinthe in the lower working class. Imitation absinthe, containing harmfully high levels of
neurotoxic antimony and copper sulfate that produced a syndrome labeled “absinthism” soon
ﬂooded the market. Public outcry against all absinthe use led to bans in Europe and the United
States by 1912.
Caffeine, Alcohol, and Sweeteners • 181
African grain beers, Betso, Buza
In Africa, much ﬁnger millet (Eleusine coracana), pearl millet (Pennisetum glaucum), sorghum (Sorghum bicolor), and African rice (Oryza glaberrima) is used to make beer. Finger millet’s amylase
enzymes readily convert starch to sugar, having a saccharifying power second only to barley, the
world’s premier beer grain. The superb productivity and yield of the millets and sorghum under a
variety of environmental conditions provides local peoples and industrial entrepreneurs with plant
resources to brew excellent African beers.
African beers are but one of a range of cereal beverages, many non-alcoholic, that are the result
of lactic acid bacteria and yeast fermentation. Fermentation has many nutritional advantages,
including increased availability of protein, amino acids, minerals and vitamins (especially certain
Agave, Pulque, Mescal, Tequila Agave spp.
Various species of Agave, short-stemmed succulents with a ﬂeshy leaf-base and trunk, have been
used as the source of pulque, or agave beer, made from the fermented sap. This beverage is the
national drink of Mexico. The beverages mescal and tequila, distillates of fermented pulque developed in Mexico, have been produced only since the Spanish introduced the practice of distillation.
Modern operations use cooked stem hearts, crushing them with water to make a mash, which is
then fermented. Like the terms scotch, pilsener, münchner, champagne, port, and so forth, “tequila”
is a place name applied to a beverage, in this case a mescal brandy. This town, in the Mexican state
of Jalisco, contains modern factories that produce the best brand of mescal.
The maguey or Agave americana, indigenous to Florida, Mexico, and other parts of tropical
America, is the commonest source of pulque. Other species used are A. tequilana, A. angustifolia,
and A. palmeri. From time immemorial the maguey has been cultivated for the abundant sap,
which collects in the cavity made in the heart of the plant by removal of the young central leaves.
The juice is rich in sugar when the maguey is about to ﬂower, and a natural fermentation process
can take place within the plant. Pulque is thick, milky, and slightly sweet. The smell can be off-putting but the liquid is refreshing and nutritious (rich in vitamins), and usually contains three to four
Anise Pimpinella anisum
Cultivated since 2000 BC in Greece and Egypt as a ﬂavoring for food and drink, anise is used in alcoholic beverages (anis, anisette, ouzo, pastis, raki, and absinthe).
Angostura bitters Angostura trifoliata
The bitter, alkaloid-rich bark of this tropical American tree produces angostura, which is used in
pink gins and other beverages.
Apple cider Malus domestica
Apples, the most popular temperate fruit tree crop worldwide, have ancient and complex origins,
with many cultivars today. There is evidence from the Neolithic and Bronze Age lake-dweller cultures of Switzerland that “wild” apples such as M. sylvestris were exploited.
In addition to being eaten fresh or cooked, the fruit is used for its juice, which is sometimes
fermented to “hard” cider or distilled to apple brandy. By the 12th century cider was a popular
182 • The Cultural History of Plants
drink in France. In the United Kingdom, the process of cider-making was introduced early
from Normandy, and today 70% of apple juice is fermented to apple cider. Colonists introduced cider-making to the United States in the 1600s. Although cider itself is popular, carbon
dioxide given off during fermentation may also be harnessed in a secondary bottle fermentation to give a naturally sparkling cider (cidre bouché); carbon dioxide may also be artiﬁcially
added to keg cider. Southwestern England, northwestern France, and northern Spain are centers of cider production.
Fruit Wines, Brandies, and Liqueurs
Brandies are usually distilled wines, but can also be distilled from cider. The most famous wine
brandies are those from Armagnac and Cognac in France. The exquisite ﬂavors of those brandies are due to the wines from which they are distilled and the fact that they are carefully
matured for many years after distillation. Many distilled wines are labeled as brandies with a
qualifying adjective indicating the kind of fruit from which they were distilled. Some, such as
kirsch (cherry brandy), have special names. Applejack or calvados are apple brandies distilled
Liqueurs and cordials differ from brandies in that sugar or syrup or both added to the distilled
liquid. Liqueurs also contain characteristic ﬂavors. The ﬂavorings used include leaves, roots, herbs,
fruits, and barks. Chartreuse, a ﬁne liqueur that has been made since 1605 by Carthusian monks in
France and Spain, is rumored to contain 130 different ﬂavoring agents.
Barley in beer and whisky Hordeum vulgare
As in the case of wine, no one knows when people ﬁrst began to brew beer, but the practice was well
established by the beginning of recorded history. Beer production was well-established in Mesopotamia and Egypt from least 3000 BC. Analysis of beer from tomb vessels has shown that beer production in ancient Egypt was sophisticated. Malted emmer wheat or barly grains were mixed with
ground grains that had been heated in hot water. The enzymes from the malted grains broke down
the starch in the resulting mixture, which was then fermented by yeast and bacteria to give a product perhaps similar in character to traditional African beers. The idea that Egytian beer was made
from bread is not supported by recent research.
Barley is now mostly used in malt-based beverages. When germinated in water and kiln-dried,
barley can be used as a substrate for yeast in beer. Beer was ﬁrst successfully bottled in 1736, and is
now one of the world’s most popular beverages. Over 29 million pints per day were consumed in
the United Kingdom in 1988, equivalent to 108 liters per head per annum, more than ten times the
consumption of wine.
Whisky, distilled from malted barley, was ﬁrst recorded in Scotland in 1494 by a friar buying
malt to make whisky. Now over four million bottles a day are made in Scotland. Barley is the preferred grain for malting. Nonetheless, grains of rye, Secale cereale, are rich in gluten and used to
make whisky in the United States, rye beer in Russia, and gin in the Netherlands. Wheat grains,
Triticum aestivum, are fermented to produce “weiss” or white beer, a beverage typical of Germany,
and are also distilled to vodka, which is typical of Russia.
Bog myrtle, Sweet gale Myrica gale
The leaves of this nitrogen-ﬁxing shrub, a common plant of wet heaths of North America,
northwestern Europe, and northeastern Siberia, are used to ﬂavor and improve the foaming
Caffeine, Alcohol, and Sweeteners • 183
Grapes in wine Vitis vinifera
Grapes are woody vines cultivated for their fruit, which is eaten fresh, dried, or drunk as a juice or
fermented. By deﬁnition, wine is any fermented fruit juice; however, in practice, the term “wine” is
overwhelmingly used for the fermented juice of grapes. The simple act of collecting ripe grapes and
merely bruising or crushing them can cause fermentation to occur due to the naturally occurring
yeast on the fruit skin. Although some scientists think it is possible that man began making wine as
early as 8000 BC, the ﬁrst concrete evidence of wine making comes from residues found in clay vessels from western Iran that have been dated to 5500 years ago.
Cultivated clones probably arose in southwest Asia and have been grown since the 4th millennium BC in Syria and Egypt and since 2500 BC in the Aegean region. The Egyptians used wine primarily for religious ceremonies, but it was only between 2000 and 1000 BC that wine became a popular
beverage in Greece. The cultivation of wine grapes spread from the eastern Mediterranean to France
at roughly about 600 BC, and later to Spain, Portugal, and Algeria. Columbus introduced plants into
the West Indies on his second voyage, and the Spanish began cultivation in California around 1769.
By middle of the 19th century, viticulture had established a special foothold in California. Australia,
the United States, Argentina, and South Africa are now among the top wine-producing countries.
The spread of grape vines to the New World saved the European wine industry from collapse
after an outbreak of Phylloxera rootlouse in 1867 that devastated European orchard stock. The
American species were reintroduced and used as resistant stocks, especially V. labrusca. There are
dozens of classical cultivars of V. vinifera—for example, the reds pinot noir and cabernet sauvignon,
and the whites chardonnay and riesling—and many are grown for wine in the major European
wine-growing nations of France, Spain, Italy, and Germany.
Grape wine has been associated with religion and other ceremonial acts since antiquity. The
ancient Greeks drank diluted wine, and wine is part of the Christian sacrament. The consumption
of wine beverages has become an intrinsic feature of Western society. Grape wines are fortiﬁed with
brandy or other alcoholic beverages in order to make sherry, port, and Madeira, and the distillation
of grape wine produces brandy. With added herbs and spice ﬂavorings, grape wine produces vermouth and martinis.
Hops Humulus lupulus
The female ﬂowers of the hop plant are the most widely used ﬂavoring agent in beer, in which it is
important both for the bitter resins that balance the sweet taste of malt, and for the essential oils
that enhance the aroma.
Wild hops are climbing plants found in fens and riverbanks in Europe. Archaeological evidence
suggests that wild hop ﬂowers were ﬁrst used in brewing in the early Middle Ages, from about 700 AD.
Cultivation of hops is well documented in historical sources in Germany from about 850 AD. Hops
were not used in ancient Egypt, and were rarely used in southern Europe, which is primarily a
wine-drinking region. Hops quickly became the dominant beer additive of central Europe and were
widely traded, but in areas of northwest Europe where sweet gale fruits (Myrica gale) were collected
and used, there was resistance to the use of hops. Hops were not widely used by English brewers
until the late 15th century, but in time a series of beer protection laws led to the use of sweet gale
being banned in Germany and other countries.
The hop plant is dioecious; that is, the male and female ﬂowers are borne on separate plants.
The female ﬂowers are borne in dense cone-like clusters. Each cone contains numerous leaf-like
bracteoles, and at the base of each bracteole there are many small lupulin glands containing resins and essential oils. The resins are responsible for the bitterness of hops, and are made up of a
184 • The Cultural History of Plants
number of alpha and beta acids, including humulone and lupulone. The essential oils contribute
to the aroma of the beer. Hops also have antimicrobial, preservative qualities, and the better traveling and keeping qualities of hopped beer were an important factor in its displacement of sweet
gale as a ﬂavoring agent.
In cultivation, hops were trained onto poles or (nowadays) onto wires. Dwarf forms of hop that
are easier to harvest are becoming increasingly important. Hops are locally important crops in several temperate areas, including the western United States, the southeast and Midlands of Britain,
and Germany and Czechoslovakia. Around 50 percent of the world hop harvest is used in extract
form, in which the ﬂavoring compounds are extracted with ethanol or liquid carbon dioxide.
Juniper Juniperus communis
The common juniper, a shrub of northern temperate zones, produces a sweet aromatic fruit used
for ﬂavorings, especially in gin and liqueurs. Over 200 tons, collected in wild places in Central
Europe, are imported annually into the United Kingdom.
Maize in beer, Chicha, Bourbon Zea mays
The majority of uses of maize, a cultigen with a complex genetic history, are for food and industrial
products. However, various traditional peoples in the Andes and Mexico continue to produce a
beverage from the food form that is both nutritious and slightly alcoholic. Chicha, or maize beer, is
produced by fermenting hydrolyzed cornstarch. Cornstarch cannot be directly fermented, and must
ﬁrst be enzymatically converted to sugar, which can be fermented. Central and South American
Indians learned that chewing corn kernels and spitting the quids into the corn mash produced an
alcoholic beverage. This action introduces a salivary amylase that hydrolyzes, or breaks down, the
starch into sugar.
Maize is an important adjunct in modern brewing operations, and overcoming this problem
of starch conversion is critical to industrial fermentation. Cornstarch is hydrolyzed to yield the
corn syrup sugars, glucose and fructose. Sour mash made from corn is a major ingredient in the
production of bourbon.
See: Grains, p. 54
Manioc, Cassava, caxiri Manihot esculenta
Known by its more popular food product names, yucca, cassava, farinha, manioc, and tapioca, the
tubers of M. esculenta yield starch and sugar, which are produced into alcoholic beverages called
kaschiri. Cassava is a shrubby tree with large tuberous roots that are rather immune to insect attack
because of the high levels of cyanide in the tuber skin. There are many cultivars with differing
amounts of cyanide. The poison is removed by squeezing the grated and ground tubers in water
and then heating or evaporating the products. The starchy juice pressed out of ground cassava is
fermented, or it is chewed in the starchy form, which aids the change into sugar.
See: Roots and Tubers, pp. 68–9
Palm wine and arrack Arenga, Borassus, Corypha, Nypa, and Phoenix spp.
The inﬂorescences of palms, when scratched with a knife, exude a sugary sap. This sap is copious
due to the large size of palms, and humans learned to gather this sweet liquid to produce jaggery
sugar and alcoholic beverages. Naturally occurring yeasts in the environment start fermentation