Jeg skal snart til at skrive SRP om koffein i kaffe og te og har valgt fagene Kemi A og historie A. Jeg har meget svært ved at finde litteratur til kemidelen, altså det rent kemiske omkring koffein, så håber i kan hjælpe?
Kan du ikke bruge denne artikel. Den er fra databasen "Science in Context", fra Gale.
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Den artikel indeholder overordnet en masse om kemien i koffein. Se også litteraturlisten jeg har vedlagt tilsidst i teksten.
Citat fra artiklen:
Caffeine, scientific name methylxanthine, is an alkaloid found in coffee, tea, chocolate, and other natural foods. It is also a component of cola soft drinks. Caffeine has been a part of the human diet for many centuries and is one of the most widely used central nervous system stimulants worldwide. In recent years, research has raised questions about possible deleterious health effects of caffeine, but no definitive conclusions have been reached about the harmfulness of moderate amounts.
Chemistry of caffeine
Caffeine is a member of the alkaloid family, a group of compounds obtained from plants whose molecules consist of nitrogen-containing rings. In general, alkaloids tend to have identifiable physiological effects on the human body, although these effects vary greatly from compound to compound.
Caffeine’s chemical name is 3,7-dihydro-1,3,7-trimethyl-1H-purine-2,6-dione. It is also known as theine, methyl theobromine, and 1,3,7-trimethylxanthine. Its molecular formula is C8H10N4O2 • H2O, and it consists of bicyclic molecules derived from the purine ring system."
Litteraturliste til artiklen:
Beckett, Stephen T. The Science of Chocolate. Cambridge: Royal Society of Chemistry, 2008.
Chambers, Kenneth P. Caffeine and Health Research. New York: Nova Biomedical Books, 2009.
Crawford, Ben. Built for Caffeine. Auckland, New Zealand: Beatnik Publishing, 2013.
Kushner, Marina, and Marina Kushner. The Truth About Caffeine. Miami, FL: SCR Books, 2011.
Pendergrast, Mark. Uncommon Grounds: The History of Coffee and How It Transformed Our World. New York: Basic Books, 2010.
Preedy, Victor R. Caffeine Chemistry, Analysis, Function and Effects. Cambridge: Royal Society of Chemistry, 2012.
Romano, Franceso D., and Pietro F. Russo. Caffeine Consumption and Health. New York: Nova Science, 2012.
National Geographic Society. “Caffeine—What’s the Buzz?.” http://science.nationalgeographic.com/science/health-and-human-body/human-body/caffeine-buzz.html (accessed February 24, 2015).
ELLER DENNE HER ARTIKEL FRA SAMME BASE (OGSÅ KUN ET CITAT):
Drugs and Controlled Substances: Information for Students, March 12, 2012
Content Level = Intermediate
Official Names: Caffeine
Street Names: None
Drug Classification: Stimulant, not scheduled
Caffeine is an alkaloid that produces a mild to moderate stimulant effect. It is naturally occurring in some foods and beverages, but is also used as an additive in some products. Evidence of caffeine use exists as far back as the Stone Age. In the early twenty-first century, beverages such as coffees, teas, energy drinks, and soft drinks are globally common means of daily caffeine ingestion by children and adults. Some widely used traditional and modern alternative medicines, as well as modern pharmacological medicines, also contain caffeine.
Legend has it that the stimulant effect of the coffee bean was first noted by an Ethiopian shepherd guarding his flock, a thousand years ago. Sufi monks steeped the berries in hot water and found that the brew helped them stay awake for long nights of prayer. Meanwhile, written records show that, during the Tang dynasty, which lasted from the seventh to the tenth century, the Chinese were already steeping and consuming tea as a beverage believed to lengthen life.
By the Middle Ages, coffee was a popular drink of Muslims. In fact, the word coffee is derived from the Arabic qahweh (pronounced kahveh). It was the Turks, however, who controlled much of the world's trade in coffee by the Middle Ages. The Turkish Empire, attempting to expand into Europe, laid siege to Vienna in 1683. The war failed, but the retreating Turks left behind 500 sacks of coffee beans, which an entrepreneur used to open the first coffeehouse in Vienna. Thereafter, coffee use spread throughout Europe."
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