Beverages

1) Stimulating Beverages - Coffee, Tea, Cocoa

Beverages such as coffee, tea, and to a lesser extent cocoa or hot chocolate have become so integral to our daily routine and social life that we take them for granted.  Of the three, coffee is the most consumed beverage in the world and is second to petroleum in terms of its importance and value traded annually on the international market.  Even if you are not a coffee drinker, you probably know many others who could not face a new day without that first cup of coffee in the morning.  The chemical stimulant in coffee, tea and cocoa is primarily caffeine which causes physiological reactions in humans that stimulates the heart and causes a rise in metabolic rate.      

a) Coffee.  Coffee is made from the roasted seeds of the coffee plant whose scientific name is Coffea arabica from the family Rubiaceae.  The origin of coffee has been traced to the forested highlands of southern Ethiopia where wild strains can still be found. The word coffee is believed to have been derived from the Arabic word "qahwa".  Although coffee is mentioned in Arab medicinal literature by the 10th century, the actual cultivation of wild coffee plants is believed to have occurred as early as A.D. 575.  By the 15th century, coffee cultivation had started in Arabia via Yemen. The introduction of Coffea arabica to Yemen from Ethiopia was believed to have been via the trade routes across the Gulf of Aden. From there coffee rapidly spread throughout Muslim world.  Coffee was introduced to Europe by the Turkish merchants of the Ottoman Empire in the 17th century.  Read this # (required) National Geographic website on Coffee Origins (click on Coffee Legends).

Sun versus shade coffee:  During the Green Revolution of the 1960s-1970s, changes in growing techniques made the production of coffee more ecologically devastating to the environment. The traditional practice of growing coffee under a shade canopy was replaced by new hybrids that could tolerate sun and give higher yields.  These new sun coffee also needed more chemicals to grow.  The elimination of shade meant elimination of habitat for wildlife especially birds species.  In the late 1990's, a growing environmental awareness sparked a renewed interest in returning to growing shade coffee that are sustainable have low impact on the environment (Conservation International).  Read this Seattle Audubon's article on # (required) Shade grown Coffee and Migratory Birds.  What is the link? .  Also read Defender's Magazine:  Coffee Made In The Shade.

b) Tea.  While tea is not as important commercially as coffee in terms of value in international trade, tea is the second most commonly drunk liquid in the world after water.  Native to China, tea comes from the leaves of Camellia sinensis (family Camilliaceae) regardless of whether tea is the green or " Oolong" or the normal ( black) type.  The chemical content and flavors of each type are different due to their respective fermentation processes. Green tea leaves are processed by withering the leaves in hot air then pan-frying to halt oxidation or (fermentation). The leaves of Oolong tea leaves are wilted in the sun and allowed to partially oxidized.  Black teas leaves are fermented in cool, humid rooms, until the leaves are black.  Under cultivation, tea is an evergreen shrub that is usually trimmed to below six feet in height.  In the wild, tea plants can reach a height of 30 feet.    

The drink is obtained by steeping the wilted leaves of C. sinensis in hot water.  Tea drinking is nearly 5,000 years old.  A legend has it that, in 2737 B.C. a Chinese emperor accidentally drank tea when some tea leaves accidentally blew into his pot of boiling water.  From China, the cultural practice of drinking tea spread to India and Japan.  In Japan, tea assumed an important role in the Zen Buddhist ritual as reflected in the Japanese tea ceremony.

Tea became popular in Europe and the American colonies in the 1600s.  Tea played an important role in American history with the famous Boston Tea Party (December 16, 1773) protesting the British tea tax -- one of the acts leading to the Revolutionary War.

Commercial plantings of tea in India by the British occurred between 1818 and 1834.  Today, India is the largest producer of tea in the world.  Sri Lanka became the second largest producer of tea in the world after the failure of coffee plantations destroyed by coffee rust that swept the area after 1880.  As a result, tea replaced coffee as the favorite beverage of the British.  The custom of infamous British tea time was purported to have been started by the aristocracies in the early twentieth century.  At tea time, tea and cakes were used to bolster energy in the late afternoons.  The practice was adopted by the upper class, the wealthy, and subsequently by all of Britain.  Drinking iced tea is a recent innovation of the early twentieth century by Americans and so is the concept of tea in a bag.  Read the Stash Website about # (required) The History of Tea.

c) Cocoa or Chocolate.  Cocoa is America's contribution to the world's nonalcoholic beverages even though eating chocolate has surpassed drinking cocoa in popularity.  Cocoa is obtained from roasted seeds (beans) of the cacao fruit.  Cacao plant, Theobroma cacao (family Sterculiaceae) is native to Central and South America.  The Mayans believed cacao to be of divine origin and "Theobroma" literally means "food of the gods."

Columbus and his crew first encountered cacao when they landed in Nicaragua.  It was not until Hernando Cortez's visit to the Aztec court that the importance of cacao in the New World was realized.  The beans (seeds) of the cacao were roasted and grounded to powder and mixed with red peeper and other spices to form a paste.  The dried paste was cut into tablets which could then be dissolved in hot water for a drink.  Cortez later introduced cacao to Europe but it was not well appreciated until the Europeans substituted the spices with sugar.  By mid 1700s, sweetened hot chocolate drink became the rage in Europe.  The Spanish established cacao plantations in the West Indies while the Dutch grew their in South East Asia. Read the Field Museum of Natural History Website on # (required) History of Chocolate and Manufacturing Chocolate.     

2) Alcoholic Beverages

Unlike stimulating beverages like tea and coffee, alcoholic beverages are produced by microbial fermentation rather than endogenous chemical in the plants.  In addition, alcohol acts as a depressant instead of as stimulant on the human physiology.  The method of producing alcoholic beverage has been independently discovered and adopted by almost all society in the world.

Beverage alcohol is produced by the action of a yeast which is a fungi in the genus Saccharomyces. In general, beverages that are derived from fermented fruit juice is called wine.  However, commercially speaking, "wine" usually refers to fermented grape juice from Vitis vinifera. Wines from other fruits are specifically referred to by the name of the fruit of the juices from which they are fermented.  Beer is obtained from fermentation of malt derived from the digestion of germinated barley grains.  Read Dr. George Wong, U. of Hawaii Website on # The Role of Yeast in Wine and Beer Making.

a) Wine.  There is a botanical evidence that suggests that the grape species used for making wine was first domesticated in western Asia at around 4000 B.C.  Grapes contain water and fructose, a monosaccharide or simple sugar.  Wine was used by the Egyptians for religious ceremonies.  The Greeks made wine a popular beverage.  At around 600 B.C., wine grape cultivation spread from the eastern part of the Mediterranean to Algeria, Spain, Portugal and France.  Columbus introduced grapes to the New World on his second voyage and the Spanish began cultivating wine grapes in California in 1769.  In 1860, The European wine industry was seriously threatened the root aphid, Phylloxera.  Unintentionally introduced to Europe from North America, this aphid devastated the susceptible European vines that precipitated a search for resistant vine rootstocks from America.  Today, almost all of the European vines are grafted onto the American resistant rootstock.  Although still world leaders in quality of wine production, Europe and north Africa are facing fierce competition from the United States, Argentina and Russia today. 

b) Beer. Beer is made from fermented grain primarily barley.  When humans first started brewing beer is a guess but it is thought that  early brewing is linked with bread baking.  An early way to make grains digestible is by sprouting them.  The sprouted grains were dried and ground into flour.  Dough from such flour would make a good medium for yeast growth and fermentation. No doubt early beers brewed this way would not be consistent in quality from batch to batch because of the variability in the wild yeast available.  Today, beer brewing is a perfected art that makes use of three basic ingredients, barley malt, hops, and water. Beer history for kids (optional)

c) Sake.  Sake the traditional rice wine of Japan is actually a beer because it is made from fermented grain which in this case is rice (Oryza sativa).  The fermentation is done by Saccharomyces cerevisiae but the breakdown of the rice starch into simple sugar is done by the fungus, Asperillus.

d) Chicha and pulque.  In Central and South America, corn can be fermented into beer called chica.  The corn is chewed and thus is mixed with salivary amylases that breaks down the starch into simple sugars.  The chewed mass of corn is mixed with water and allowed to ferment in a container.  In other areas of Central America, several species of Agave is used to make alcoholic beverage called pulque.  The Agave plant is harvested at the stem base and the leaves trimmed off.  The stem base is baked, mashed, mixed with water and then allowed to ferment to form pulque.  The Spaniards taught the native to distil pulque into tequila and mescal.  Pulque is still produced today in various parts of Mexico.  To learn more about tequila, read this article by Cedeno and Alvarez-Jacobs on  Production of tequila from agave: historical influences and contemporary processes (Not required).     

After completing Unit II Section A, please click on Section C.

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