Nowadays, coffee is a favorite of many young people.


However, how much coffee a person drinks a day is the category of health?


To buy prepackaged coffee products, you should carefully check the product label and pay attention to the shelf life and production date. When buying roasted coffee beans.


One is "take a look", the appearance of good quality coffee beans is bright and shiny, the size and shape are similar.


Second, "smell", good quality coffee beans have a strong aroma and no peculiar smell.


Third, "taste", better quality coffee beans are chewed crisp and sound.


Fourth, "pinch", good quality coffee beans are solid.


Prepackaged coffee products should be stored in accordance with the conditions indicated on the product label.


Roasted coffee beans, it is best to keep the whole beans sealed, as far as possible to maintain the aroma of coffee, to avoid damp or accelerated deterioration.


Coffee beans that have been ground are best brewed and drunk within 2 weeks.


If stored for a short time, it can be stored in a cool and dry place.


If stored for a long time, it can be frozen and sealed in the refrigerator at 18 ℃


After being removed from the freezer, it should be kept at room temperature for a period of time, and the coffee beans should be ground when the temperature is close to room temperature.


Coffee contains caffeine, chlorogenic acid, trigonelline and other bioactive components.


Caffeine is a xanthine alkaloid compound and a central nervous system stimulant.


Excessive intake may cause insomnia, irritability, nervousness, irritation, blushing, polyuria and gastrointestinal discomfort.


In addition to controlling coffee consumption, if you consume tea, tea drinks, milk tea, chocolate, cola, and other caffeinated foods, you should reduce coffee consumption accordingly.


The best time to drink coffee is in the morning. Do not drink before going to bed, so as not to affect sleep.


Fasting state as far as possible not to drink coffee, because coffee can stimulate gastric acid secretion, and too much gastric acid is easy to damage gastric mucosa.


After caffeine intake, it reaches a peak in 30 to 60 minutes.


When your body metabolizes half of the caffeine, it usually takes three to five hours, and the rest of the caffeine will stay in your body for longer.


Because caffeine is metabolized by the liver, a person with a bad liver can metabolize caffeine more slowly, and the unit can even change from hour to today.


Generally speaking, it is ok to drink three or four cups of coffee a day. As the powder content and extraction rate of each cup of coffee are different, the caffeine content of each cup of coffee may not be the same.


The specific calculation formula is as follows: the weight of coffee powder used * extraction rate * caffeine content of coffee beans.


You can calculate your caffeine intake for a day by using this formula.