The caffeine content of high-density black coffee is higher than that of ordinary black coffee. Caffeine content depends on many variables, such as beans, baking degree, grinding degree, extraction temperature, extraction method, extraction time, powder-water ratio, powder-water dosage, whether milk and water are added for subsequent dilution and other factors. The caffeine content of Robusta beans per kilogram is almost twice that of Arabica beans.

The efficacy and function of black coffee

Moderate drinking of black coffee has the functions of refreshing, enhancing thinking ability and restoring muscle fatigue; At the same time, it can increase heart rate, raise blood pressure and relax smooth muscle.

Black coffee refers to coffee drinks without milk or sugar. The main effective component of coffee is caffeine and its structural analogue theophylline. Caffeine is a central nervous system stimulant, which has a strong central excitatory effect. Moderate use can eliminate fatigue and excite nerves, and is clinically used to treat neurasthenia and coma.

In addition, caffeine can also enhance the working ability of human skeletal muscle. For example, after drinking coffee for 40 minutes, the concentration of fatty acids in human blood will rise to the highest, which is the best time to lose weight by exercise, because fatty acids will promote the decomposition of fat and make exercise more effective.

However, large doses or long-term use can also cause harm to the human body, especially addiction. Once stopped, there will be various withdrawal symptoms such as mental fatigue, fatigue and weakness.

Need to be reminded that coffee has a remarkable refreshing effect and should not be drunk before going to bed. Studies have also proved that 2 hours after drinking coffee, free fatty acids in the blood will increase and blood sugar will rise, so people with chronic diseases such as hypertension and hyperlipidemia should not drink it.