The three most important are coffee, tea and cocoa. All three are stimulating beverages, all contain caffeine and related compounds.

It is not clear if health problems are caused by consumption of moderate amounts of caffeine. Heavy consumption can cause anxiety, dizziness, insomnia, and heart palpitations. Inclusion of caffeine in soft drinks is a questionable practice since children have low body mass and consume large quantities of soft drinks.

Coffee

Coffea - native to E. Africa, used first in Ethiopia although coffee is not widely used in Africa now.
Arabs were first to brew coffee and use spread from Arabia to Egypt and then to Europe. Coffee was particularly popular in England
Arabs monopolized trade by boiling seeds to kill them but Dutch and French were able to obtain seeds and grow the trees themselves. Brazil currently leads the world in coffee production.

Coffea arabica - 90% of world's production
C. canephora -9% - Robusta coffee
C. liberica - 1% - Liberian coffee
The last two are hardier plants than C. arabica and C. canephora produces more fruits but C. arabica still predominates. C. arabica is a self-compatible polyploid, other are self-incompatibile diploids with a more bitter flavor.

Coffee fruit is an accessory berry - the floral cup, exocarp, mesocarp and endocarp are called the parchment. Each fruit contains 2 seeds = beans, mostly endosperm.

Coffee is grown in tropical and subtropical climates with fertile soils and 75" rainfall but requires dry season for flower development. Trees begin producing and 3 years and produce for 40 years. Coffee is usually picked by hand.

Processing - Seeds are separated from fruit, fermented and roasted

Light roast
Dark Roast - stronger flavor due to roasting at higher temperature, beans are oily-appearing because high temperature brings oils to surface.
Most coffees sold in U.S. are light and medium-roasted.

Instant coffee - ground beans are brewed under pressure, high temperature basically ruins coffee flavor. Freeze drying is one method of producing instant from liquid.

Decaffeinated coffee is produced by three different methods.
1. Solvent extraction - methylene chloride is used to remove caffeine, solvent is removed (hopefully) during roasting. Caffeine is removed from solvent with water and crystallized.
2. Water extraction - green beans are percolated with water that contains all water-soluble compounds found in coffee with exception of caffeine, more expensive than solvent extraction.
3. Steam extraction - recent, secret procedure.

75% of purified caffeine (2 million pounds) is used in soft drinks, rest in headache and cold medicines.

Cichorium intybus (chicory) is most common additive to coffee.

Cacao

Theobroma cacao - chocolate and cacao, New World origin in eastern Andes, "Food of the Gods" to Mayans, Mayan drink included cacao, red pepper and other spices.

Sweet hot choclate became very popular in Europe in 17th century. Spanish, then Dutch, then Germans became involved in establishment of cacao plantations. Africa is now world's largest producer.

Cacoa plants are small trees grown in shade, the pods contain 20-60 seeds, are broken open and cleaned by hand. Seeds are fermented which changes their white color to purple. Seeds are very bitter at this point. Seeds are then roasted, cracked to remove seed coats to yield nibs (cotyledons), nibs are ground, making enough heat to melt fat and produce choclate liquor which can be molded into baking choclate.

Cocoa is made by pressing out fat (cocoa butter), dry powder is treated with alkali to produce Dutch cocoa.

Milk chocolate is produced by continuous stirring of a mixture of choclate liquor + cocoa butter + sugar + condensed milk.

Tea

Camellia sinensis - probably native to China, cultivation and use of tea originated in Asia.

Portugese introduced tea to Europe in 16th century, tea was important trade item in Europe by 18th century. Colonial Americans were fond of tea and were angered by tea tax imposed by British which resulted in the Boston Tea Party.
Tea time was initiated by Duchess of Bedford in early 20th century.
Cultivation - has not been grown successfully in New World except Argentina, most tea is grown in Asia. Plants are small evergreen trees which require good rainfall and cool temperatures. Trees are pruned to force bushlike growth. Picking is by hand, youngest leaves and terminal bud only are picked, plants can be picked once a week. Tea bags were initially used as samples.
Green tea - leaves are shredded, heated, dried and packaged, used locally.
Black tea - produced by fermentation process, tea for international market
Oolong - fermented for short period.
Iced tea - origin at 1904 St. Louis World's fair

Other Beverages

Mate - Ilex paraguariensis - Holly family, from southeastern S. America, evergreen, leaves are dried and crushed, traditionally drunk from a hollow gourd plain or with sugar. A local plant, Ilex vomitoria, is used to make cassina tea.

Guarana - Paullina cupana - used by Amazon Indians, seeds are roasted and crushed, 2nd only to coffee in Brazil.

Kola - Cola nitida - relative of cacao, original Coca Cola had Coca and kola, seeds are cleaned and allowed to ferment, then dried and pulverized to a powder, seeds also contain kolanin (heart stimulant)

Root beer - carbonated, sweetened beverage flavored by extracts (caramel, sarsaparilla, wintergreen)

Sassafras albidum - aromatic bark used to make medicinal tea, may be carcinogenic.

Herb teas - made from a variety of fragrant plants

Ginseng - Panax quinquefolium - use roots roots to make tea, straight tea does not taste very good so is usually used with honey or herb tea. Thought to have many positive affects, especially by Orientals.

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