How much caffeine is in different drinks?
Caffeine (also matinein, guaranin) is a purine alkaloid, colorless or white bitter crystals. It is a psychostimulant found in coffee, tea and many soft drinks. Caffeine is found in plants such as coffee tree, tea, cocoa, mate, guarana, cola, and some others. It is synthesized by plants to protect against insects that eat leaves, stems and grains, as well as to encourage pollinators.
Most people have limited knowledge of caffeine, for example: "There is a lot of it in coffee, less in tea." This is fundamentally wrong. In fact, there are unexpected nuances. We decided to see how much caffeine is contained in one standard serving of the drinks you know. And also we compared this amount with a safe daily norm of 300 mg caffeine.
Cup of tea
Cup of green tea
Cup of black tea
Bank Mountain Dew
Cup of espresso
Instant coffee mug
Grande Cappuccino from StarBucks
- Systematic Name: 1,3,7-trimethyl-1H-purin-2,6 (3H, 7H) -dione
- Traditional names: 1,3,7-trimethylxanthine, guaranine, caffeine, matein, methylteobromine, thein
- Chem. formula: C8H10N4O2
- Rat formula: C8H10N4O2
- State A solid crystalline substance is colorless or white, odorless.
- Molar mass 194.19 g / mol
- Density 1.23 g / cm3
- Melting point: 234 C
- T. Subl .: 180 C
- pKa: 1.22
- Dipole moment: 3.64 D
- Reg. CAS Number: 58-08-2
- PubChem: 2519
- Reg. EINECS Number: 200-362-1
- RTECS: EV6475000
- ChemSpider: 2424
- LD50: 192 mg / kg (mice, oral)
- Toxicity: moderately toxic
In animals and humans, it stimulates the central nervous system, enhances cardiac activity, accelerates the pulse, causes the expansion of blood vessels (mainly vessels of the skeletal muscles, brain, heart, kidneys), enhances urination, reduces platelet aggregation (however, in some cases, the opposite effects are noted) . This is due to the fact that caffeine blocks the enzyme phosphodiesterase, which destroys cAMP, which leads to its accumulation in cells. cAMP is a secondary mediator through which the effects of various physiologically active substances, primarily adrenaline, are realized. Thus, the accumulation of cAMP leads to adrenaline-like effects.
In medicine, caffeine is used in the treatment of headaches, with migraines, as a stimulant of respiration and cardiac activity in colds, to increase mental and physical performance, to eliminate drowsiness.
Dosages for the appointment of caffeine should be selected individually. Higher doses for adults inside: single 0.3 g daily 1.0 g, intravenous single 0.4 g daily 1 g
Caffeine is on the list of vital and essential drugs.
It was discovered and named “caffeine” in 1819 by the German chemist Ferdinand Runge. In 1827, Udry isolated a new alkaloid from tea leaves and called it thein. Pure caffeine was first obtained in 1828 (Pelletier and Cavantou). In 1832, its composition was established by Weller and Pfaff and Liebig. In 1838, Jobst and G. Ya. Mulder proved the identity of thein and caffeine. The structure of caffeine was clarified by the end of the 19th century by German Emil Fischer, who was also the first person to artificially synthesize caffeine. He won the 1902 Nobel Prize in Chemistry, which he received in part because of this work.
Chemical structure and properties
The chemical name for caffeine is 1,3,7-trimethyl-xanthine. In an alkaline environment (at pH> 9), C7H12N4O is converted to caffeine. In structure and pharmacological properties, caffeine is close to theobromine and theophylline; all three alkaloids belong to the group of methylxanthines. Caffeine acts better on the central nervous system, and theophylline and theobromine - as stimulants of cardiac activity and lung diuretics. Caffeine, like other purine alkaloids, gives a positive murexide reaction; when heated with Nessler's reagent, caffeine forms a red-brown precipitate, unlike theobromine, which gives a light brown color in such conditions.
White needle crystals of bitter taste, odorless. It is soluble in chloroform, poorly soluble in cold water (1:60), easy in hot (1: 2), hardly soluble in ethanol (1:50). Solutions have a neutral reaction; sterilized at +100 C for 30 minutes T pl. 234 C.
Illustrator Natalya Roshchenko