Outline and Readings Sugar Coffee Tea Chocolate p. 55 sugar Chap 16.
Sugar What we call “sugar” is sucrose, a disaccharide made of glucose plus fructose. –“sugar” is actually a more generic term for a whole series of simple carbohydrates The name “carbohydrate” comes from the approximate composition: a ratio of 1 carbon to 2 hydrogens to one oxygen (CH 2 O). For instance the sugar glucose is C 6 H 12 O 6. Carbohydrates are composed of rings of 5 or 6 carbons, with –OH groups attached. This makes most carbohydrates water-soluble. Glucose, a monosaccharide or simple sugar, is the primary food molecule for generating energy. Other compounds get converted to glucose, then get broken down into carbon dioxide.
Oxidation of Glucose Energy from chemical bonds is transferred in the form of electrons. The process is called oxidation and reduction. Cells oxidize glucose to form carbon dioxide and water. The cell removes high energy electrons from glucose (in a series of steps), which converts it to carbon dioxide. The energy stored in the electrons is used to make ATP, the cell’s energy molecule. The electrons (now low energy) are given to oxygen molecules, converting them to water. By passing the electrons through a series of steps before their final destination in water, the cell can harvest the energy efficiently. In contrast, burning releases the energy all at once, so it can’t be captured easily.
Sugar in Animals and Plants Sugar is a source of the food calories we need, and we are genetically programmed to enjoy eating it: we have a taste receptor for sweetness. –So are most animals (even insects), although cats have lost their sweetness taste receptor and are pretty indifferent to sweet things. In plants, sucrose is used to transport sugar through the phloem from the leaves to other tissues. In most plants, the sucrose gets converted to starch for storage, or converted to glucose to be used as food. However, sugar cane (and sugar beets) stores the sucrose.
Sugar Cane in the Ancient World Sugarcane (Saccharum officinarum) is a monocot, a tropical perennial grass with C4 photosynthesis. Sugar cane originated in New Guinea, probably as a hybrid of several different species. people chewed the stalks for the sweet taste Spread throughout East Asia (including India) and the Pacific Islands as much as 5000 years ago the Indians learned how to crystallize sugar from the sugarcane sap –Basic method: pound the sugar cane stalks to extract the juice, then boil it to concentrate the sugar. It crystallizes out, far purer than the original sap. In 350 BC: Alexander the Great noticed “honey obtained from reeds” during his conquest of western India, and brought it home to Greece.
Sugar, Islam, and the Crusades Muslim traders and conquests following 632 AD spread sugarcane cultivation as far west as Spain. Also, they developed methods for large scale industrial production of sugar. In Europe, the only sweetener was honey. During the Crusades (1100's), Europeans came across "sweet salt", and by 1200 sugar was considered a necessary (but expensive) commodity in Europe. –It was still an expensive spice, however. In 1319 AD it went for the equivalent of $50 per pound.
Sugar in Europe Europeans started growing it on Cyprus and on various islands in the Atlantic: Canaries, Cape Verde Islands, Madeira. All these islands were discovered, or re-discovered, by the Portuguese in the 1400's as they attempted to work their way around Africa under the leadership of Prince Henry the Navigator. In August 1492, on his first voyage to the still-undiscovered New World, Christopher Columbus stopped at the Canary Islands to pick up fresh food and water. He intended to stay only 4 days, but he became romantically involved with the governor of the island, Beatriz de Bobadilla y Ossorio, and stayed a month. When he finally left, she gave him some sugarcane cuttings, which became the first European plant to reach the Americas.
Sugar in the New World Sugarcane likes tropical climates, and the Caribbean worked very well. Unfortunately, smallpox, yellow fever, and malaria were rampant: these are all Old World diseases. Disease and hard work killed off the enslaved native population. This created a huge market for African slaves, who had more natural resistance to the diseases. –But, the death rate was very high: more than 4 million slaves were brought into the British West Indies starting around 1700, but there were only 400,000 slaves when slavery ended in 1838. The combination of slavery, good climate, and improved production methods drastically increased the availability of sugar, and lowered the price. Sugary foods really caught on after 1700: in 1700, the British consumed 4 pounds of sugar per person in a year. By 1800 it was 36 pounds per person. By 1750, sugar was the most valuable commodity in European trade.
Triangular Trade Triangular trade: profit on every leg! –Trade goods (cloth, metal pans, guns, etc.) shipped from England (later, Boston) to west Africa and used to buy slaves. –Slaves shipped across the Atlantic to the Caribbean, where they were sold to sugar plantations This was the Middle Passage, and 15% or more died on the way. –sugar (often in the form of molasses) shipped to England (or later, Boston). The sugar was refined, and the molasses was distilled into rum. In 1763, at the end of the Seven Years’ War (French and Indian War), France chose to give Britain control of Canada (“a few acres of snow”) in exchange for the Caribbean islands of Guadaloupe and Martinique. The American Revolution (1780's) was greatly helped by the fact that the British considered the sugar-growing Caribbean islands far more valuable than their North American colonies. Thus, they put many troops and resources in the Caribbean and not in North America.
Sugar Beets Sucrose is also found in beets, but not in large amounts. –The same beet (Beta vulgaris) as the vegetable, but not red. During the time of Napoleon (1807), the British blockaded French ports, so no sugar could be imported from the Caribbean. This led to the development of the sugar beet industry in France. Selective breeding increased the sucrose concentration by a lot: 15-20% sucrose. In the continental United States, sugarcane only grows in Florida, Texas, and Louisiana. However, sugar beets are much hardier. Thus, most US sugar is made from sugar beets. Today, about 30% of world sugar comes from sugar beets.
Planting and Harvesting of Sugarcane Sugarcane is a hybrid that does not breed true, so commercial crops are reproduced from vegetative cuttings. It is a perennial, but after several cuttings it doesn't produce as well, so the roots are removed and new cuttings planted. Sugarcane is harvested by cutting close to the ground: highest concentration of sugar there, and then stripping off the leaves, which interfere with processing. Mechanical harvesting (aided by improved plant varieties) only got started in the 1950's. Even now, half of the world’s sugarcane is cut and stripped by hand. It is very labor-intensive.
Sugar Mill Cane must be processed within 24 hours or the sucrose content drops. Thus, the sugarcane is pressed in a mill close to the fields. Sugar mills chop and shred the cane, then press it to extract the juice. Lime is added to remove impurities (which float to the top and are skimmed off). The clarified liquid is concentrated by heating it to evaporate water. The juice crystallizes into a sticky dark brown sugar, which is then shipped to a refinery for purification. –In colonial days (1650-1850) the British had a high tax on importing refined sugar, so the Caribbean sugar plantations shipped the unrefined sugar to England. The remaining plant material is dried and burned to heat the evaporation pans. Sugar mills produce more energy than they use.
Refining Sugar Unlike most foods, sugar is a single chemical compound, sucrose. The more refined sugar is, the fewer contaminants (other compounds) are mixed in with the sugar. One bit of chemistry: pure compounds form crystals, which are just regular arrays of the molecules stacked up together. When crystals for, other compounds are excluded from the crystal structure. So, crystallization is the basic method for purifying sugar. The sugar refinery condenses the juice by boiling it until sugar crystals form. Pure refined sugar involves dissolving the sugar in water, then clarifying it by adding lime. This process precipitates out impurities and colored material. The clarified liquid goes through several cycles of being concentrated by heating under a partial vacuum until the sugar crystallizes, extracting the crystals by centrifugation, then redissolving them. Done under very clean conditions.
More Sugar Refining The liquids left over after crystallization is molasses. Still contains some sucrose, but also various minerals, proteins, and other nutrients. –Molasses can be fermented into heavy beers like stout, or distilled into rum. In pre-modern times, sugar was separated from molasses by pouring the dissolved sugar into conical molds with a hole in the bottom. Over several days, the remaining molasses drained out the narrow end. The sugar could also be washed by pouring sugar water on the top end and letting it drain. You end up with a sugar loaf. 10 inches in diameter, 30 inches tall, weigh 35 pounds or so. Modern methods involve using a centrifuge to rapidly separate the crystals from the liquid.
Stimulants Coffee, tea, and chocolate all contain caffeine, a chemical compound that stimulates the central nervous system. –Tea also contains theophylline and chocolate also contains theobromine. These compounds are similar in their chemical structure and their effects to caffeine. Caffeine speeds the heartbeat, raises blood pressure, relieves drowsiness and restores alertness. Because of this, they are widely used throughout the world. –90% of adult Americans consume caffeine daily. –Even in pre-historic times, people chewed plants for the caffeine United States v. Forty Barrels and Twenty Kegs of Coca- Cola. A 1911 Supreme Court case that tried to get caffeine labeled as a deleterious and habit-forming substance. It was rejected by the courts. Also, bills were introduced in the House of Representatives to accomplish the same thing; they failed. –Caffeine is legal almost everywhere in the world. –The US Food and Drug Administration (FDA) classifies caffeine as “generally recognized as safe” as a food additive.
Caffeine Effects Caffeine binds to the adenosine receptors in the brain. What adenosine receptors do isn’t clear: they seem to slow mental activity, promote sleepiness, and increase blood flow in the brain. –Caffeine acts as an inhibitor of the adenosine receptor neurons People develop tolerance and dependence on caffeine: it takes increasing doses to get the same stimulation. This is because the number of adenosine receptors is greatly increased in people who routinely use caffeine: “up-regulation”. When caffeine is withdrawn from an addict, the extra adenosine receptors cause the blood vessels in the brain to dilate, leading to headaches and nausea.
Coffee Coffee comes from the seeds of a shrub that is native to Ethiopia in eastern Africa. There are two species grown commercially: Coffea canephora (called robusta) and Coffea arabica, plus a few others in minor usage. –C. arabica accounts for 85% of commercial coffee; C. canefora is stronger and harsher, and is mostly used for instant and decaffeinated coffee. Most arabica plants are self-pollinating and highly inbred. Thus, they vary little from plant to plant and can be grown from seed. In contrast, C. canephora is self- incompatible so it must be outcrossed. As a result, every seedling is genetically different from every other, and useful varieties must be propagated vegetatively.
History of Coffee The (probably mythical) origin story: Kaldi the Ethiopian Goatherd noticed the energizing effects of raw coffee berries on his goats and tried them out. He took the berries to a local holy man, who disapproved and threw them into the fire. When the beans started roasting, they smelled so good that Kaldi and the holy man raked them out of the fire, ground them up and put them in hot water: the world’s first cup of coffee. Coffee was probably used in Ethiopia after about 100 AD, by eating whole berries or by crushing and mixing them with fat. It was energy food for warriors. The first real evidence of coffee brewing as we know it today is from the mid-1400’s, in Sufi monasteries in Yemen (southern part of Arabian peninsula). –Very helpful for staying awake during long religious ceremonies –From there it spread to the rest of the Muslim world: Egypt, North Africa, Turkey, Middle East, Persia.
More History Coffee reached Europe through trade between Venice and the Ottoman Empire. It became fashionable among wealthy Venetians about 1600 AD. Coffee drinking was initially prohibited by both Muslim and Christian (Ethiopian Orthodox) religious leaders, but the bans were reversed after important political leaders started to enjoy it. –Various priests wanted Pope Clement VIII to ban it, but after trying a cup, he baptized it, making it an acceptable drink for Christians. After this, it spread rapidly throughout Europe, and coffeehouses became popular gathering places, sources of intellectual stimulation. –The insurance company Lloyd’s of London was founded in a coffeehouse. –Political leaders didn’t like this. Charles II of England called coffeehouses “seminaries of sedition”. Not everyone liked this. Here’s part of a petition from 1645:...the Excessive Use of that Newfangled, Abominable, Heathenish Liquor called COFFEE [...] has [...] Eunucht our Husbands, and Crippled our more kind Gallants, that they are become as Impotent, as Age
Coffee Leaves Africa In the 1600’s, the Arabs monopolized the coffee trade, by dipping the beans in boiling water to kill them before selling them. The Dutch managed to obtain some live plants in the late 1600’s, and found that they grew well in Indonesia (the island of Java) and Ceylon (Sri Lanka). The trees also grew well in greenhouses in Amsterdam and Paris. Coffee came to the Americas after a ship’s captain talked the botanist in Paris out of some cuttings: the botanist was reluctant to disfigure the King’s coffee tree. From there, cultivation moved to other parts of the Caribbean and South America. Today, the largest coffee producers are Brazil and Vietnam.
Growing Coffee Originally, coffee was grown in the shade of open forests. However, in recent times, coffee is grown industrially in open sun, with high fertilizer and pesticide usage. This results in higher yield and more rapid ripening, but probably lower quality. Coffee plants are killed by frost, but they grow best at high elevations, where the plants grow more slowly and acquire more flavor. –C. canefora can grow at lower elevations, and it is resistant to rust. The plants start producing berries at about 3 years, and they can be productive for about 40 years. Coffee berries are the fruits of the coffee bush. The berries contain the “beans”, which are actually the seeds. Each berry contains 2 seeds.
Processing Coffee Ripe berries are picked, and the flesh is removed. The beans are coated with a sticky layer of mucilage, which is removed by soaking the beans and allowing naturally-occurring enzymes to degrade the mucilage for several days. –This is called “fermenting”, but it is entirely different from the fermenting used to produce alcoholic beverages. –Fermenting helps develop the proper taste. The beans are then washed (which produces a large amount of waste water), and dried. The result is green coffee beans. The green beans are then graded and sold for export. The green beans need to be roasted: most coffee is sold in the roasted state, not green. This is done at about 200 o C, for about 15 minutes. Roasting promotes many chemical reactions in the beans, causing them to develop their flavor, color, and aroma.
Decaffeinated and Instant Coffee Instant coffee is made by dehydrating brewed coffee. –The original process involved spraying the coffee in a fine mist in a dry tower. Water evaporated from the droplets as they fell to the ground. –Freeze-drying is a more recent process that retains the flavor better: the brewed coffee is frozen, then dried under a vacuum. About 20% of coffee consumed in the US is decaffeinated. There are several decaffeination processes. –Invented by a German, Ludwig Roselius, who believed his father had died from too much coffee drinking. –Originally, green coffee beans were steamed, then soaked in methylene chloride. This removed the caffeine without affecting the flavor much. However, methylene chloride was found to be carcinogenic and banned. –Another method involves soaking the beans in liquid carbon dioxide, which can only be done under pressure. –The Swiss Water method involves soaking the beans in water that in saturated with all the compounds present in coffee except caffeine. This causes the caffeine to diffuse out of the beans, while the other compounds stay inside.
Coffee Rust Coffee rust, a fungal pathogen, is native to Africa. It was first reported in 1861. wiped out the coffee plantations in Ceylon between 1867 and 1869, and spread from there to India and other Asian countries. –They were replaced by tea plantations. This switched the British from coffee drinkers to tea drinkers. Rust also knocked out most of the Indonesian coffee production, where rubber replaced coffee as the main cash crop. Spread to South America (Brazil) in 1970. Coffee is the obligate host for this organism, so its spread is helped by monoculture: growing nothing but coffee in the fields (i.e. sun-grown). Some chemical control, especially by copper compounds. But mostly controlled by catching the infection early and destroying the infected plants. Current work: breeding resistant varieties.
Tea Tea is thought to be the most widely consumed beverage in the world. –“Herbal tea” or “tisane” are terms used for any number of dried plant mixtures that are prepared by soaking in boiling water. Most of them contain no real tea. The tea plant, Camellia sinensis, seems to have originated in Southeast Asia, where China, Burma (Myanmar), Tibet, and India intersect. Shen Nung, the semi-legendary second Emperor of China (about 2727 BC), invented Chinese agriculture and medicine. He is said to have been drinking a bowl of boiled water, when some tea leaves fell in. He noticed the pleasant taste and stimulating effect: the first cup of tea.
Growing Tea The tea plant is a shrub that is generally kept pruned to 3-4 feet tall, for easy harvesting. Historically, it was grown from seed, but today it is propagated vegetatively to maintain genetic uniformity in high quality varieties. Tea itself is made from the leaves and buds of the tea plant. Specifically, the bud and top two leaves are used to make the best teas. The plants are usually plucked twice a year, often by hand.
Processing Tea Although all tea comes from the same plant, it can be processed four (or more) different ways, to produce green tea, black tea, oolong tea, and white tea. The basic processes used in tea processing are: –Withering is done as soon as the leaves are harvested, to remove water from the leaves. Blowing hot dry air on the leaves for 12-24 hours does this. –Oxidation involves letting the leaves sit in a climate- controlled room for several days, during which enzymes in the leaves break down the chlorophyll and do other chemical conversions. Sometimes called “fermentation”, but no microbes are involved. –After oxidation, the leaves are subjected to fixation, but heating them briefly. Fixation stops the oxidation process. –Rolling breaks open the cells, releasing the flavors.
Types of Tea The differences in the types of tea come from whether they are allowed to wither before drying, and whether they are allowed to oxidize. Black tea, the main type used in the US, is withered for 12-24 hours, then fermented for 2-4 weeks. –In China, black tea is called red tea, because that is the color of the brewed tea liquid. Oolong tea is only partly fermented, for 2- 3 days. Green tea is not fermented. As soon as it is picked, the oxidation process is stopped by steaming the leaves. Then it is rolled and dried. The green color come from chlorophyll. White tea is lightly steamed to destroy the enzymes that cause oxidation, but not fermented.
History of Tea Domesticated in China very long ago, and widely consumed. But, it was grown in inaccessible places, and odd stories about it existed. –Supposedly, in one village monkeys pick the tea. The villagers stand below the tea tree and taunt the monkeys. The monkeys respond by gathering handfuls of leaves and throwing them at the villagers. –Or maybe it’s trained monkeys Spread to Korea, Japan, and the rest of East Asia by Buddhist priests, roughly 600 C.E. –The Japanese tea ceremony was invented by Zen Buddhist monks, as a way of demonstrating the universal truths that are found in simple things. Tea existed in India, but mostly as medicine, not as a popular drink.
Tea Comes to Europe Tea was brought to Europe by Dutch traders in the 1600’s, but caught on slowly. In 1662, Charles II of England married Catherine of Braganza, a Portuguese princess. She grew up drinking tea, and it became a fashionable drink at court under her. Around 1700, the British East India Company started an advertising campaign to increase tea’s popularity –Because of Catherine of Braganza, tea drinking was acceptable for women, although coffee drinking was not. –Also at this time, sugar from the Caribbean became much cheaper. –Sweet tea became very popular. The drink of the Industrial Revolution: the caffeine is a stimulant and the sugar provides energy.
More Tea History During the late 1700’s, tea got so popular in England that the British East India Company (BEAC) had to pay the Chinese in silver, not trade goods. –The solution: BEAC started growing opium in India and shipping it to China illegally. –The Chinese government objected, and started the Opium Wars. Advanced British weapons dominated, and the Chinese were forced to officially accept opium in trade for their tea. The Chinese did not allow the export of tea plants, or knowledge of how to process it. The BEAC hired a botanist, Robert Fortune, who dressed up as a Chinese official and started looking for the tea-growing regions. –The people there had never seen a European, so they thought he was just a weird looking guy from a distant province. –Fortune smuggled live tea plants to India, where they grew very well. India was the world’s leading tea producer up until very recently.
Tea in America Tea was a popular drink in colonial days: we were a British colony. Its import was a monopoly, but much smuggling occurred. An attempt to stop the smuggling and enforce the BEAC monopoly led to the Boston Tea Party in 1773, where Bostonians dressed up as Mohawk Indians boarded some ships and threw a lot of tea overboard. It was a precursor to the American Revolution (1776). After this, it became unpatriotic to drink tea in the US for many years: coffee was drunk instead. Iced tea was invented in 1904, during a heat wave at the St. Louis Exposition. Only drunk in the US. –Also invented at this time: the ice cream cone The tea bag was also invented in 1904. It was cheaper than packaging the tea in tin cans, and made brewing the tea much easier. Originally made of silk.
Chocolate Comes from the cacao plant, Theobroma cacao. Native to New World tropics. –The coca plant, source of cocaine, is an entirely different plant despite similar names. Used as a ceremonial beverage by the Mayans and Aztecs, but very different from the modern sweet chocolate: bitter and mixed with hot peppers and other spices. They also mixed it with tobacco and smoked it. –The genus Theobroma means “food of the gods” Cacao beans were used as currency among the Aztecs. There were even counterfeit beans in circulation. –Example: 1 turkey was worth 100 cacao beans Unfortunately, the Spanish conquerors destroyed nearly all written records from these civilizations, so most of our knowledge is archeological and not historical. Marriage feast in 1051 AD (Nuttall Codex)
Chocolate and the Europeans Columbus originally brought it back to Spain, but it wasn’t really understood: just some more odd looking seeds. When Hernan Cortez conquered Mexico in 1519, he met (and killed) the ruler Montezuma. Cortez noted how the beverage was prepared, and that Montezuma drank vast quantities of it. The Spanish added sugar was added to make it fit European tastes. It was an expensive drink. –However, it wasn’t as popular as tea or coffee, partly because it had a high fat content and thus made a rather greasy drink. Chocolate houses, equivalent to coffee houses, sprang up in England in the late 1600’s. The chocolate bar was invented in about 1828, after the method of removing cocoa butter from cocoa powder was invented.
Growing Cacao The cacao tree is a found in the understory of tropical forests, perhaps originally from the Amazon River basin. It likes a warm, wet, and shady environment. Wild cacao trees still grow in South America. Cacao is pollinated by tiny flies (midges). One of the problems with commercial cacao production is that the midges are hard to transplant, and getting the flowers pollinated has been difficult. –A mature tree can have 6000 flowers on it, and only produce 20 pods. The largest production is in western Africa, especially the Ivory Coast, Ghana, and Nigeria. –Indonesia also produces a lot, and South America still produces significant quantities. –Children are often used, and often not paid i.e. they are slaves.
Harvesting and Fermenting Chocolate is made from the seeds (called “beans”) of the cacao tree. The seeds are contained within pods (the fruits), which contain about 50 seeds. Ripe pods are harvested manually, and the seeds plus surrounding pulp are removed, The seeds and pulp are allowed to “ferment” (oxidize) for a week. They are left out in the open or covered with banana leaves, and stirred periodically. The chocolate flavor only develops during fermentation: green beans have no chocolate taste. After fermenting, the seeds are dried and sent to a chocolate factory
Chocolate Factory At the factory, the beans are roasted to develop the flavor and color. Most beans are treated with alkalai (“dutched”) to neutralize natural acids and produce off tastes. The chocolate actually comes from the fleshy cotyledon leaves of the seed. After roasting, these “nibs” are removed from the seed coat and embryo. The nibs are then ground up and heated to melt the cocoa butter: they are up to 40% fat. The result is a thick liquid called chocolate liquor or cocoa mass. –When allowed to cool, the chocolate liquor can be sold as unsweetened baker’s chocolate.
More Chocolate Processing Cocoa butter is separated from cocoa powder by pressing the chocolate liquor. –Cocoa butter is the main ingredient of white chocolate, and it is also used for cosmetics, suntan lotion, and other things. It has very little chocolate taste or color. –Cocoa powder is also sold as unsweetened cocoa, for baking. Chocolate bars are made by mixing cocoa butter, cocoa powder, sugar, and vanilla. Milk is also added, for milk chocolate but not dark chocolate. –The mixture is then “conched”: mixed mechanically for several days to develop a smooth velvety texture. Chocolate is often mixed with other ingredients.
Kola The kola nut is made by a tree native to tropical Africa (Kola nitrida). It is related to the cacao tree (native to South America). –The fruits are pods containing 8 seeds. Processing involves removing the seed coats and allowing a fermentation to occur. Kola nuts contain caffeine, and it is chewed as a stimulant and appetite suppressant in many West African cultures. –They are extremely bitter. Visitors to a home are offered kola nuts as part of a ceremony. Also sometimes as part of a wedding ceremony: gifts from a groom to the parents of the bride.
Coca-cola Coca-cola was invented in 1886, in Atlanta,Georgia. It contained extracts from coca leaves (source of cocaine) and from kola seeds, as well as caramel color, sugar, carbonated water, and several other ingredients. –After 1903, cocaine was removed from the coca leaves, although they are still used as a flavoring. Recipe is locked in a bank vault and is highly secret. –The main flavor comes from cinnamon and vanilla. An attempt in 1985 to improve the flavor, called New Coke, was a spectacular failure. Many people preferred the original flavor despite market research taste tests that suggested the opposite. Or perhaps it was just a problem with a change in something familiar.
Soft Drinks Coca-cola was just the first example of carbonated, caffeine- containing beverages. Many are marketed around the world, with different flavors depending on local tastes. –Most don’t use kola nuts as a source of caffeine: it’s too bitter. Most Illinoisans call soft drinks “pop”, but in other parts of the country, it’s called “soda” or “coke”.
Maté and Guaraná Maté is traditional South American drink, the national drink of Uruguay and popular in Argentina and Paraguay. It contains significant amounts of caffeine and is used as a stimulant similar to coffee. Maté is made by steeping the leaves of yerba mate (Ilex paraguariensis) in hot water. It is sucked through a steel straw with small holes at the end to act as a sieve, from a hollow gourd. It is often drunk in social groups, as part of conversation. Guaraná is also a caffeine-containing plant native to South America. Ground seeds are immersed in hot water to make a tea. It is used in the Amazon forest of Brazil. –The word “guaraná “has become a synonym for soft drinks in Brazil. The seeds are often used as a flavoring in these drinks.