Coffee’s best known agent is an alkaloid called caffeine. In smaller amounts caffeine can be found also in tea, cola nuts and cocoa.

Caffeine effects:

  • increases heart rate, metabolism and respiration
  • increases blood pressure and blood circulation speed
  • dilates cerebral blood vessels
  • narrows the blood vessels in the intestine
  • diuretic
  • eliminates drowsiness
  • improves mood
  • stimulates the cerebral cortex
  • accelerates the thinking process
  • it causes a temporary increase in performance, followed by a sudden decrease in performance.

Caffeine can be detected in almost every tissue of the body 5 minutes after drinking a cup of coffee. Its concentration reaches its maximum in half an hour and then slowly decreases. After 3-6 hours, the concentration is about half of the maximum.

A large dose of caffeine (over 300 mg) causes hand tremors, blood clots, and pressure around the heart. In addition to caffeine, there are many acids in coffee that affect the taste of coffee. For example, 2-methylvaleric acid is responsible for the chocolate flavour, and red-vinyl acid for the caramel flavour.