Coffee

Martina Ehrenbergerová

Zuzana Mišovie

Abstract

Abstract

History of coffee

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What is coffee?

Caffeine

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History of coffee

Coffee was known in 15th-century Arabia; from there it spread to Egypt and Turkey, overcoming religious and political opposition to become popular among Arabs. At first proscribed by Italian churchmen as a heathen's drink, it was approved by Pope Clement VIII, and by the midlle17th cent. coffee had reached most of Europe. Introduced in North America c.1668, coffee became a favorite American beverage after the Boston Tea Party made tea unfashionable.

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What is a coffee? Coffee as a drink, usually served hot, is prepared from the

roasted seeds (beans) of the coffee plant. It is one of mankind's chief sources of the stimulant caffeine. Because of this, coffee's nutritional benefits are disputed, sometimes labeled a cure-all, other times labeled a health hazard (see caffeinism).

Coffee is a popular beverage made from beans of the coffee

tree, which have been cleaned, dried, roasted, ground, and brewed with water to extract their flavor.

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beans

Caffeine

Soon after drinking a cup of coffee, or tea or cola, caffeine is distributed throughout the body. As it is similar to substances normally present in the tissues, caffeine could affect all the systems of the body: nervous, cardiovascular, respiratory and so on. However, caffeine does not accumulate in the body, so its effects are short-lived and transitory.

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Caffeine Caffeine is an alkaloid. There are numerous compounds

called alkaloids, among them we have the methylxanthines, with three distinguished compounds: caffeine, theophylline and theobromine.

Caffeine 1,3,7-trimethylxanthine Theophylline

1,3-dimethylxanthine Theobromine

3,7-dimethylxanthine

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Caffeine as a drug

- Caffeine is present in many prescription and non-prescription (over-the-counter) drugs, including some taken for headache, pain relief, appetite control, staying awake, colds, asthma and fluid retention. The caffeine contents of drugs varies from 7mg to 200mg per tablet.

- Customary caffeine consumption has been classified as follows:

Low caffeine users: less than 200mg per day Moderate caffeine users: 200-400mg per day High caffeine users: more than 400mg per day

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Toxic dose

-The LD_50 of caffeine (that is the lethal dosage reported to kill 50% of the population) is estimated at 10 grams for oral administration. As it is usually the case, lethal dosage varies from individual to individual according to weight. Ingestion of 150mg/kg of caffeine seems to be the LD_50 for all people. That is, people weighting 50 kilos have an LD_50 of approx. 7.5 grams, people weighting 80 kilos have an LD_50 of about 12 grams.

-In cups of coffee the LD_50 varies from 50 to 200 cups of coffee.

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roasted-pražený

beans-zrniečka

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ground-povrch

flavour-aróma

served-slúžil

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transitory-dočasný

fluid-tekutina

retention-zadržanie

dose-dávka

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Thanks a lot for your attention

The End