At all times and among all nations the value of fruit and berries for food rated very highly. Berries, as well as processed products contain a variety, including the biologically active substance: digestible sugar, glucose, fructose, sucrose, polysaccharides, organic acids, mineral salts, vitamins, flavoring substances and pectin. 

The chemical composition of berries is not constant, but it varies during their growth, maturation, and also depends on the species, varieties, harvesting time, the conditions and duration of storage of fruits. Berries contain not only the necessary nutrients for the body carbohydrates, mineral salts. They are also a major source of vitamins. Vitamins promote the development of the body, protect us from disease, enhance performance and endurance.

When they are not in a food or they are in small amounts, the vitamin deficiency occurs. People in such cases feel a weakness, get tired quickly and complain of insomnia. The vitamin deficiency is sometimes observed if people have at long monotonous diet, even if they eat foods with high calories.