1. Inorganic substances

Water has important significance for the human organism, since it is the component part of its cells and cloths and it is necessary for the realization of biochemical processes. It plays important role in the maintenance of a constant temperature of body. To adult person it is necessary in average 1750-2200 g of water in a 24 hour period. This need is covered, first of all, due to the drinking water and the food. Living organism is very sensitive to a deficiency in the water: severe indisposition is experienced with loss by 10% of moisture of men, while death begins with loss by 20%.

Water is located in all products, but in different quantities: in the sugar - 0,14%; in the flour - 12-14; in the bread - 40-50; in the meat, the fish - 65-80; in the vegetables, fruits -65-95%, and etc.

They conditionally divide into the free and connected the water, which is contained in the foodstuffs. It significantly influences the nourishing value, the fitness for the storage, the taste, the consistency of products. The products, which contain a large quantity of free water, relate to those being perishable, since it is favorable medium for the microorganisms and products rapidly undergo damage (putrefaction, molding, fermentation). On the contrary, the products, in which it is small water, are more posting in the storage. At the same time the products, rich in moisture, have the low energy value (although their biological value can be high). Each product must contain water in the specific quantities, what provided in many standards is one of the basic qualitative exponents. Depending on the special features of products themselves, and also conditions of environment they can lose moisture or, on the contrary, be moistened. The high hygroscopic (ability to absorb moisture) possesses sugar, salt, flour, dry fruits and vegetables, caramel and other products. The decrease of moisture in the fresh fruits, the vegetables, the boiled wurst, the meat, the fish and others during the storage leads to lowering in the quality and commodity losses.

The definite requirements are presented to the drinking water. It must be clean, transparent, colorless, without the smell, outside aftertastes and harmful microorganisms, the moderate hardness or soft.

Mineral substances are otherwise called ash elements, since after the combustion of product they remain in the form ashes. Ash elements have great significance for the vital activity of the human organism: they enter into the composition of cloths, they participate in the exchange of substances, in the formation of ferments, hormones, digestive juices. Deficiency or absence of separate elements in the organism leads to the severe illnesses. To the human organism be required in a 24 hour period 20-30 g of ash elements.

Depending on the content in the products ash elements divide into macro cells (calcium, phosphorus, sulfur, potassium, sodium, iron, magnesium, chlorine and others) and the micro cells (iodine, copper, aluminum, zinc, cobalt, manganese, fluorine and other). Are separated also ultra-micro cells (radium, thorium, mercury and others). Each of the mineral substances plays the leading role in the vital activity of organism. For example, phosphorus participates in the respiration, it is necessary for the normal activity of nervous system and work of muscles; potassium contributes to isolation from the organism of water and salts of sodium; iron participates in the formation of hemoglobin of the blood; iodine ensures the normal activity of the thyroid gland; manganese and fluorine contribute to the formation of the bones and etc.

Some elements are necessary for the organism in very small quantities (copper, lead, zinc, tin and others) and with their content in significant quantities become poisonous and dangerous for the life. The especially large danger in this respect presents the conserve foodstuffs, processed in the copper equipment and which were being stored in the hermetically sealed metallic banks for a long time. Therefore the content of copper, zinc, tin strictly is limited in food products, but the presence of salts of mercury, lead, and arsenic is not allowed.

The sources of mineral elements are products of plant and animal origin, and also drinking water. Are especially rich in mineral salts the vegetables, the fruits, grain flour, the products of sea and others.

Ash content is the qualitative index with the determination of the type of flour, starch, and also is characterized the value of the surface finish of product (sugar, cocoa- powder).