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Chemistry of Coffee



Coffee is one of the drinks of natural origin, consisting of a large number of different substances that strongly affect the human body. 50% are aromatic compounds that make up the taste of the beverage. A truly rich and filling taste that you can taste with freshly brewed coffee beans that have only been roasted in less than a month. After the coffee is roasted, it starts to lose its richness of flavor.


Coffee beans contain a large amount of complex organic matter. These substances and their changes in the coffee-making process are being studied by dozens of different research laboratories around the world. The aim of the work is not only to understand the chemical composition of substances and their transformation at various stages of preparation, but also to improve technology, to look for methods that will provide coffee of the highest quality. The composition of raw cereals includes caffeine, trigonellin, chlorogenic acid, protein and mineral salts. However, this set of substances, whose names say little to a person far from chemistry, makes up about a quarter of the mass of raw grain. The rest comes from fiber, coffee oil, and water.


Now we will talk about the chemical composition of coffee.


Caffeine is an element of the group "Alkaloids", stimulating the work of the central nervous system. Caffeine - got its name from "coffee", as it was first obtained from coffee beans. The tonic effect in coffee drinks is provided by caffeine.

Caffeine is found not only in coffee beans, but also in tea leaves and cola nuts. Experts believe that two bottles of Coca-Cola tonic drink prepared from these nuts are equivalent to one standard cup of coffee in terms of its effect on the human body. Not everyone knows that the same mass of tea contains twice as much caffeine as coffee. Still, you'll find half as much caffeine in a cup of tea as in a cup of coffee. There is no contradiction here. Real,

The second alkaloid found in coffee beans is trigonelline. It does not have an exciting feature, but it plays an important role in the formation of the taste and smell of roasted coffee.

The question may arise about the role of caffeine and other alkaloids in plants. There is nothing superfluous and necessary in nature. According to experts, caffeine appeared in coffee trees in the process of evolution to protect plants from harmful insects, because this substance is a natural pesticide.


Experiments have shown that powdered tea and coffee strongly influence the behavior and development of many insects and their larvae. Concentrated doses lead to their death.


When the green coffee beans are roasted, the water is first removed and the content is reduced from 11% to 3%. Sugar caramelization occurs. The sucrose in the beans is converted into caramel under the influence of heat, giving a brown color to the coffee infusion. Insoluble polysaccharides are partially broken down into simpler, soluble carbohydrates.


In the process of roasting, a very complex substance is formed - caffeine, with which a particular coffee flavor is associated. Its content reaches 1.5% in roasted coffee. Cafeol was isolated by distillation of roasted coffee with superheated steam. This is the most complex substance, in which there are more than 220 components by modern methods. Numerous attempts to artificially create a substance with coffee flavoring have not yet led to significant success. But everyone will agree that aroma is the soul of coffee. High roasting temperature does not affect the caffeine content. It is fully preserved, and even the percentage of caffeine increases, as the mass of the coffee bean decreases during roasting. Trigonellin is destroyed during frying, and a significant amount of nicotinic acid is formed in the decomposition process. This complex organic substance is one of the B group vitamins. Vitamins in this group play an important role in the biochemical processes occurring in the living organism and prevent a number of serious diseases such as pellagra. It has long been noted that in parts of South America, where the population is constantly suffering from malnutrition, the practically non-existence of pellagra lies in the coffee bean, which contains nicotinic acid. After all, coffee is the national drink of the peoples of Latin America and is consumed there in large quantities. Coffee contains more than thirty different organic acids (including malic, citric, acetic and caffeic). One of them is chlorogenic - it is only found in significant quantities in coffee beans. Its content in them varies from 4 to 8%, depending on the variety. Its content in fruits and leaves of other plants is negligible. Chlorogenic acid decomposes when roasted to form other organic products that give coffee its characteristic, slightly astringent taste. The presence of various acids in coffee has a positive effect on stomach activity and improves digestion. The peculiarity of coffee and the presence of complex organic substances - tannins. They give a bitter taste to the coffee drink. Milk and cream, which are often added to coffee, interact with tannins to bind them, then the coffee partially loses its bitterness. Also keep in mind that the caffeine is almost completely transferred into the beverage when brewing coffee. Coffee Numerous attempts to artificially create a substance with its aroma have not yet led to significant success. And everyone will agree that this aroma is the soul of coffee. High roasting temperature does not affect the caffeine content. It is fully preserved, and even the percentage of caffeine increases, as the mass of the coffee bean decreases during roasting. Trigonellin is destroyed during frying, and a significant amount of nicotinic acid is formed in the decomposition process. This complex organic substance is one of the B group vitamins. Vitamins in this group play an important role in the biochemical processes occurring in the living organism and prevent a number of serious diseases such as pellagra. It has long been noted that in parts of South America, where the population is constantly suffering from malnutrition, the practically non-existence of pellagra lies in the coffee bean, which contains nicotinic acid. After all, coffee is the national drink of the peoples of Latin America and is consumed there in large quantities. Coffee contains more than thirty different organic acids (including malic, citric, acetic and caffeic). One of them is chlorogenic - it is only found in significant quantities in coffee beans. Its content in them varies from 4 to 8%, depending on the variety. Its content in fruits and leaves of other plants is negligible. Chlorogenic acid decomposes when roasted to form other organic products that give coffee its characteristic, slightly astringent taste. The presence of various acids in coffee has a positive effect on stomach activity and improves digestion. The peculiarity of coffee and the presence of complex organic substances - tannins. They give a bitter taste to the coffee drink. Milk and cream, which are often added to coffee, interact with and bind the tannins, after which the coffee partially loses its bitterness. Also keep in mind that the caffeine is almost completely transferred into the beverage when brewing coffee.

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