Coffee: what it consists of and how it works

The Arab doctor and alchemist Razes, even before 1000 AD, described in his writings the healing properties of the Binchum drink, that is, coffee. In the East, it was believed that coffee accelerates thinking, amuses the heart, and helps against eye diseases, gout, dropsy and scurvy.

The Italian doctor and botanist Prosper d’Alpino, who accompanied the Venetian embassy in Egypt in 1592, strongly recommended this drink as a first-class medicine in his treatise on coffee. It is also known that one of the court healers prescribed in 1665 to the Russian Tsar Alexei Mikhailovich the recipe: “Brewed coffee, famous by the Persians and Turks, and ordinary after lunch … a fair amount of medicine for arrogance, rhinitis and headache”.

Coffee beans contain a large amount of complex organic substances. Each type of coffee has its own special combination of substances. Raw coffee beans include caffeine, trigonellin, chlorogenic acid, protein and mineral salts. This set of substances, whose names, however, say little to a person far from chemistry, makes up about a quarter of the mass of raw grain. The rest is fiber, coffee oil, and water. In addition, green coffee beans contain essential essential fatty acids that are healthy: linoleic – 52.2-54.3%; linolenic – 2.2-2.6%; palmitic – 26.6-27.8%; oleic – 6.7-8.2%; stearic – 5.6-6.3%; arachidonic – 2.6-2.8%; behenic – 0.5-0.6%.

According to its chemical composition, caffeine is one of the representatives of the alkaloids group. It is to him that coffee owes its stimulating and invigorating effect. In its pure form from coffee extract, this substance was isolated in the 20s of the last century. Caffeine has the appearance of colorless crystals with a bitter taste. The structural formula of caffeine was deciphered at the end of the 19th century, and in 1897 it was synthesized by the German chemist G. Fischer in its purest form. 

It has long been known that in small doses, caffeine excites the central nervous system, primarily due to stimulation of the cerebral cortex, which leads to an acceleration of general metabolism, increased respiration and blood circulation. Caffeine is part of many pharmaceuticals manufactured by the pharmaceutical industry. The percentage of caffeine in coffee beans depends on the variety. The largest number is found in Robusta from Guinea (1.7–2.3%), Santos (1.3–1.5%), and Hodeide (1.2%).

In order for coffee to have tonic properties, you need from 0.1 to 0.2 g of caffeine per serving (pharmacologists consider a dose of caffeine in excess of 0.25 g to be too large). Such a dose corresponds to about one to two teaspoons of ground natural coffee per glass of water. Not recommended simultaneous intake of more than 0.3 g of coffee per day. When making coffee, caffeine almost completely goes into the drink. It should be remembered that with the systematic use of caffeine and other purine alkaloids at the level of 1000 mg per day, a person develops a constant need for them, reminiscent of alcohol dependence.

Canadian doctor R. B. Har reported that in some cases he prescribed older people strong coffee before bedtime as a remedy for insomnia. It is not clear why caffeine has a calming effect, but nevertheless it is also useful for children with painfully increased activity.

The second alkaloid contained in coffee beans is trigonellin. It does not have exciting properties, but it plays an important role in the formation of the taste and smell of roasted coffee. Coffee contains more than 30 different organic acids (including malic, citric, vinegar and coffee). One of them – chlorogenic – is found in significant quantities only in coffee beans. Its content in them ranges from 4 to 8%, depending on the variety. In the fruits and leaves of other plants its content is negligible. When roasted, chlorogenic acid decomposes, forming other organic products that give coffee a characteristic, slightly astringent taste.

The presence of complex organic substances, such as tannins, is also characteristic of coffee. They give the coffee drink a touch of bitterness. Milk and cream, which are often added to coffee, interact with tannins and bind them, then coffee partially loses its bitterness.

The stimulating effect of coffee lasts up to 3 hours. It is important to note that after the excitement caused by coffee, there is no depression, as is the case with the use of alcoholic beverages.

It should be remembered that coffee does not contain caffeine in its pure form, but in a certain ratio with a large group of other organic substances. Therefore, the body’s reaction to coffee is different than when taking pure caffeine.

Under the influence of coffee, the vasomotor center is also excited, which leads to the expansion of the blood vessels of the heart, the redistribution of blood in the body, and an increase in the speed of its movement. In normotonic patients, blood pressure usually rises slightly, but in hypertensive patients this effect can be significantly higher. In people with heart failure, the extra diuretic effect caused by coffee is of particular importance. Most studies have not shown a correlation between coronary heart disease and coffee consumption, however unfiltered coffee can cause an increase in total plasma cholesterol.

Studies have shown that caffeine is effective for migraine headaches, enhances the influence of certain painkillers (in particular, aspirin and paracetamol), and can reduce the risk of Parkinson’s and Alzheimer’s disease. It should be remembered that for an adequate assessment of the possible interaction of drugs, it is extremely important for the doctor to know about regular coffee intake.

Coffee affects the functioning of the lungs, resulting in faster breathing. It affects coffee and digestion. An outstanding Swedish naturalist and naturalist of the XVIII century Karl Linney described the properties of coffee in one of his works: “… This drink strengthens the womb, helps the stomach to cook food, clears the clogged inside, warms the stomach.”

Here, mainly the organic acids contained in coffee make themselves felt. As a result of their action, the secretion of gastric juice is enhanced, and about half an hour after taking coffee, acidity reaches a maximum. This speeds up the digestion process, food is better absorbed by the body. That’s why the systematic use of coffee slightly reduces the frequency of constipation. The tradition of serving coffee for dessert is also due to this. However, the increase in acidity that occurs after taking coffee imposes a ban on this drink for those who suffer from gastritis, peptic ulcer of the stomach or duodenum.

Other effects of coffee are also known: its systematic use can improve insulin sensitivity and reduce the risk of type 2 diabetes. There is evidence that coffee may reduce the risk of breast cancer in women.

Despite all the variety of effects revealed, at present, the complex chemical processes occurring in coffee beans have not been fully studied. The role of the individual constituents, and especially the whole complex of substances, has not yet been disclosed.

Leave a Reply

Your email address will not be published. Required fields are marked *