Food products - products used by humans for food in natural or processed form.
Classification:
1. According to the source of receipt:
· animals;
vegetable;
Synthetic
2. By function in the body (according to Petrovsky):
plastic (meat, fish, milk, eggs);
energy (bread, flour and cereal products, fats and products thereof);
Regulatory or biological stimulants (vegetables, fruits, berries, fish oil);
taste (spices, spicy vegetables)
Terms used in the examination of the soundness of products.
In accordance with SanPiN 2.3.2.560-96. The following terminology is currently used:
1. The quality of food products is a set of characteristics that determines the consumer properties of food products and ensures their safety for humans.
2. Quality certificate - a document in which the manufacturer confirms the origin of food products and their compliance with the requirements of regulatory documentation.
3. Safety of food products - the absence of danger to people of present and future generations, determined by the compliance of food products with the requirements of sanitary rules and regulations.
4. Nutritional value - a complex of substances of food products that provides the physiological needs of a person for energy and basic nutrients.
5. Biological value - an indicator of the quality of a food protein, reflecting the degree to which its amino acid composition meets the body's needs for amino acids for protein synthesis.
6. Biological efficiency - an indicator of the quality of fatty components of food products, reflecting the content of polyunsaturated fatty acids in them.
7. Energy value - the amount of energy released in the human body from nutrients, food to ensure physiological functions.
According to their quality, products are divided into:
1. Benign - products that are fully consistent with their receipt and production of the State. The standard and when eaten do not cause pathological changes in the body.
· Standard (fully correspond to state standard specification);
Non-standard (does not meet the requirements of the State Standard, but does not impair the quality of the product and does not have pathogenic properties).
2. Conditionally fit - products that have a defect that makes them hazardous to health and does not allow the use of the product without pre-treatment in order to neutralize or improve organoleptic properties (they increase only due to heat treatment). Product examples: sour milk, forced slaughter meat or Finnose meat (contains larvae, 3 larvae per 40 cm2). The meat is cut into pieces no more than 2.5 kg, no more than 8 cm thick, boiled for at least 2.5 hours with a tightly closed lid, the broth is not used. Meat is used in secondary processing.
3. Poor quality - have a drawback that does not allow the use of a food product. Because it can cause death. These products can be used for feeding to livestock (by the decision of the veterinarian), disposal, destruction (burning, burial).
4. Counterfeit products - products whose natural properties have been changed in order to deceive the buyer or consumer (alcoholic beverages, meat, juices, wines).
5. Surrogates - products produced instead of natural ones (protein caviar, barley coffee, carrot tea).
Product classification by storage stability:
1. Particularly perishable - have a shelf life in the refrigerator (filled products, pate - liver, boiled kodbass, liver - blood sausages);
2. Perishable soon - a longer period (in the refrigerator), can be frozen (meat, fish, dairy products);
3. Sustainable products (not quickly perishable) do not require a refrigerator, humidity is not more than 15% (sugar, cereals).
Examination methods:
● Chemical (ph environment, foreign inclusions);
● Physical (t, viscosity, transparency, density);
● Organoleptic (color, taste, smell);
● Microscopic (morphological structure, fiber structure);
● Bacteriological (degree of microbial contamination);
● Biological;
● Radiometric (degree of radioactive contamination).
Stages of product examination:
1. Acquaintance with the documentation;
2. External inspection of the container with an assessment of its condition and forced opening (at least 10%) and each place with contamination;
3. Organoleptic study (if the first 3 points do not match, then go to point 4);
4. Sampling (we select an average sample, which should characterize the state of the entire batch);
5. Laboratory research and conclusion.
Based on the conclusion, the doctor decides: the state of good quality; recommendations for its use.
FOOD QUALITY
Food quality- this is a set of properties that reflect the ability of the product to provide organoleptic characteristics, the body's need for nutrients, safety for its health, reliability during manufacture and storage.
The nutritional value - this is a complex property that characterizes the fullness of the useful properties of the product.
Nutrition properties:
biological value characterized by the presence of biologically active substances in products: vitamins, macro- and microelements, essential amino acids and polyunsaturated fatty acids. These substances are not synthesized in the body. They are called essential and must come from food (meat, fish, dairy products).
Physiological value is determined by the ability of products to influence the nervous, cardiovascular and digestive systems of a person. Tea, coffee, spices, lactic acid and other products have this ability.
The energy value products is determined by their content of fats, proteins, carbohydrates and their digestibility. When oxidized in the body, 1 g of fat releases energy equal to 9.3 kcal (37.7 kJ), 1 g of protein - 4.1 kcal (16.7 kJ) and 1 g of carbohydrates - 3.75 kcal (15.7 kJ ). Knowing the chemical composition of the product, you can calculate its energy value.
Organoleptic value - determined by appearance, texture, smell, taste, composition, degree of freshness. Products that have a dull color, irregular shape, uneven surface, excessively soft or rough texture are absorbed worse.
digestibility- the degree of use by the body of the consumed product. Digestibility depends both on the objective properties of the product (type, taste, aroma, texture, amount of nutrients, etc.), and on the state of the body, nutritional conditions, habits, tastes, etc. The average digestibility of proteins is 84.5%, fats - 94%, carbohydrates - 95.6%. This means that the actual calorie content is always less than the calculated one.
Goodness- the absence of spoilage processes (rotting; oxidation, rancidity, salting; fermentation; the appearance of mold), the absence of pathogenic microbes, toxic strains of fungi, helminth larvae, toxic substances, harmful mechanical impurities and insect pests.
The labeling of a food product must necessarily contain information about its composition and nutritional value, conditions and shelf life.
Level of quality- quantitative and qualitative expression of the properties of products (or goods). Each indicator has a name and value (measurement result). For example, pasta quality indicators:
The standards and specifications provide for three groups of indicators: organoleptic, physico-chemical and microbiological.
Organoleptic indicators - characteristics of fundamental consumer properties, determined with the help of human senses.
Physico-chemical indicators - characteristics of the physical and chemical properties of food products, determined by physical and chemical measuring methods of testing. Determine the content of sugar, water, etc.
Microbiological indicators serve to establish the degree of contamination of the product with microorganisms. At the same time, both their total content and the type of microbes, the presence of bacteria in the product that cause food poisoning are determined.
Organoleptic indicators are the most accessible, simple, but not reliable enough, therefore, they should be supplemented with physicochemical indicators, which are distinguished by a greater degree of reliability and objectivity.
Grades of quality:
1. Suitable goods are standard goods that meet the established requirements for all selected indicators. Standard goods are divided into groups, classes, brands, numbers, grades and types. Varieties are the most widespread.
2. Conditionally eligible goods are non-standard goods that do not meet the established requirements for one or a set of indicators, but this discrepancy is not critical (dangerous). Such goods can be sold at reduced prices, used for livestock feed or for processing. Butter staff, unripe watermelons, small potatoes.
3. Dangerous Goods unsuitable for intended use. They must be destroyed or disposed of in accordance with certain rules. Goods rotten, moldy, damaged by rodents.
GOODS GRADE
The names of commercial varieties are, as a rule, impersonal. Basically there are the highest, 1, 2 and 3 commercial grades. Varieties of some goods are additionally assigned special names. For example, long leaf tea is divided into the following commercial varieties: bouquet, extra, highest, 1st, 2nd and 3rd. Varieties of rye flour - wholemeal, peeled and seeded - were assigned in accordance with the applied grinding of the same names.
With the harmonization of Russian standards with European ones, the term “variety” began to be replaced by “quality class” (for example, in standards for fresh vegetables).
In addition to dividing into commercial grades, some products are divided into groups, brands, numbers, etc.
There is no fundamental difference between commercial varieties, quality classes, brands, numbers and types. All of them are gradations of the quality of goods of the same name. Different terms have developed historically.
Quality grades for some products
| Description of goods | Gradations | Names | Features |
| cereals | Stamps | M, T, TM | Type of wheat |
| Rooms | 1 to 5 | grain size | |
| Varieties | Extra, supreme, 1st, 2nd, 3rd | The content of benign raw materials and impurities | |
| Wheat flour | Varieties | Extra, grain. Highest, 1st, 2nd, wallpaper, peeled | Ash and fiber content, color, grain size |
| Types | 8 types | Wheat type, ash and fiber content | |
| Pasta | Groups | A, B and C | Type of wheat |
| Varieties | Highest, 1st and 2nd | Flour grade | |
| Roots | classes | Extra, 1st, 2nd | Shape, color, size |
Quality control- a set of operations for choosing the nomenclature of indicators, determining their actual value and comparing them with base indicators.
Regulated values of standards or other normative documents (conformity assessment), as well as standard samples, substances, standards can be taken as basic indicators.
When comparing, the correspondence or non-compliance of the actual values of quality indicators with the base ones is revealed. This operation ends with a decision to assign a certain quality gradation to the product.
The quality of food products is a set of product properties that determine its suitability for meeting certain needs in accordance with its intended purpose. The quality of food products must meet the requirements of standards. The quality of any food product is determined by its characteristic properties, which are called quality indicators.
The most significant influence on the formation and preservation of the quality of food products is exerted by the type and quality of raw materials, methods and conditions of production, packaging and condition of containers, transportation and storage.
The quality of food products is determined by organoleptic and measuring (laboratory) methods.
The organoleptic method determines the quality of products using the senses: sight, touch, smell and hearing. This method establishes the taste, color, smell, texture and appearance of the product. At catering establishments, this method is considered the main one and is supplemented by test cooking or frying a product whose quality is doubtful. For a more objective conclusion about the quality of some products (cheeses, butter), a scoring has been introduced. Its essence lies in the fact that the quality of the product is evaluated by the sum of a certain number of points according to organoleptic indicators, taking into account discounts for defects in the product. At the same time, the main indicators characterizing the quality of the product are taste and smell. Based on the total score, the commercial grade of the product is determined. Commodity Studies: Textbook / Ed. Ed. M.V. Romanovsky. and O.V. Vrublevskaya.- M.: Yurayt, 2011.-p.114.
The measuring (laboratory) method allows using instruments, reagents to determine physical (specific gravity, density of products, their melting and freezing point, viscosity), chemical (mass fraction of moisture, proteins, fats, carbohydrates, organic acids, minerals, harmful and toxic impurities), microbiological (presence of pathogenic and spoiling food microbes), physiological properties, energy value, digestibility, food safety of the product, etc.
To study the quality, an average sample is taken - a sample of a batch of a product from different places of packaging. The sample is sometimes taken with a special probe. The procedure for taking an average sample is indicated in the standards.
In a market economy in a market saturated with goods, producing them by different enterprises and firms, a guaranteed confirmation of the conformity of the goods to a certain level of quality specified in the standard is necessary.
Such confirmation of conformity is given in the form of a certificate of conformity.
A certificate is a document confirming the conformity of product quality with the established requirements of the standard, drawn up according to the rules of the certification system. It includes: code, product type; manufacturer; place of manufacture; data on compliance with safety requirements, relevant standards or regulations; data and approval of the results in the testing laboratory, test report; data on the validity of the certificate, its registration in the register of the Company and the registration number of the Company.
Certification is the activity of independent authorized bodies of the state to confirm the quality of products in accordance with the established requirements of standards.
Certification rules are developed by Gosstandart of Russia and approved by the Law of the Russian Federation.
One of the important documents for issuing a certificate is a hygiene certificate, introduced by a resolution of the State Sanitary and Epidemiological Supervision in 1993.
The purpose of the hygienic certificate is to prevent the adverse effects on human health of hazardous foodstuffs in which the maximum permissible norms of microbiological indicators or the concentration of substances leading to the accumulation of toxins are exceeded. Hygienic certificates must have: food raw materials, food products, food additives, dyes, preservatives.
Any product manufactured in Russia with a quality certificate must have a Conformity Mark on each packaging unit - this is a sign confirming the compliance of the products marked with it with the established requirements of the standard, according to certification.
Food products in their quality must comply with the requirements of state standards, which are abbreviated as GOSTs. G.B. Pole. - M.: UNITI, 2011.- P.123.
The quality indicators of a number of products for which GOSTs have not yet been established are given in temporary technical specifications - VTU.
In the sanitary assessment of a food product, its suitability or unsuitability for food is determined.
Sanitary assessment of food products is carried out by organoleptic and laboratory methods.
In the organoleptic evaluation of the quality of products, the sense organs are used: sight, smell, touch, taste. To better determine the quality, test cooking of dubious products is carried out - meat, fish, cereals, etc. in a sealed container. A stale product has an unpleasant odor during cooking. In doubtful cases, a sample of the product is sent to the laboratory for analysis.
The laboratory research method is more accurate: it is used to determine not only the good quality of products, but also its chemical composition, calorie content, etc.
A product is considered to be of good quality if it is free of signs of spoilage, harmless to health and has an appropriate nutritional value.
In some cases, the harmful properties or impurities of the product may disappear after its appropriate processing. Such a product is considered conditionally suitable; it can be used for food only after neutralization. Conditionally suitable products include, for example, Finnish meat, which can be used as food after disinfection by boiling, curing or freezing in a slaughterhouse.
Unsuitable for food are products with irremovable harmful properties or impurities of toxic substances that are dangerous to human health.
All products entering the warehouse of the enterprise must have quality certificates. When accepting products, it is necessary to find out whether all the documents are in order, what are the deadlines for the sale of products, whether there are any special instructions in the documents regarding the sale and storage of products, for example, instructions from a sanitary worker that products can only be used after cooking. It is necessary to check the date of release of the product by the industrial enterprise, which is especially important for cooked sausages, smoked fish, cream cakes and pastries, milk and dairy products, chocolates, marshmallows, etc.
After checking the documents, food products are carefully examined to determine their good quality. The check is carried out by the storekeeper and the head of production with the participation of an employee of the departmental sanitary service (if any). Food warehouse workers and cooks should be able to determine the quality of food and know the main signs of spoilage.
Product quality is one of the fundamental components of competitiveness. The quality of goods is understood as a set of properties that make up its quality, considered in relation to certain conditions of its creation, operation and consumption. From this definition, we can conclude that its property is taken as the initial characteristic of product quality. All properties of products can be divided into simple and complex.
When assessing the quality of food products, such important indicators as caloric content (energy capacity), biological value, characterized by the content of essential amino acids, polyunsaturated fatty acids, vitamins, mineral salts, tonic substances and other biologically active compounds, as well as organoleptic properties - shape, external appearance, color, texture, taste and smell. For many products, indicators such as readiness for consumption, shelf life, etc. also play a role. The quality of the product as a whole is determined by the sum of all complex indicators, taking into account the coefficient of significance of each of them.
The study of the quantitative characteristics of the quality of food products, i.e. the totality of their properties and values for a person, a special branch of knowledge is engaged in - qualimetry Commodity science: account. Allowance for universities. Ed. N.D. Eriashvili and others - 2nd ed., revised. and additional -M.: UNITY-DANA, law and law, 2013.-p.125.
Each batch of food products coming from industrial enterprises is accompanied by a quality certificate (certificate). The quality of products in public catering establishments is established organoleptically, and in case of doubt, by a laboratory study of selected samples.
A sample that allows you to judge the properties and merits of the entire batch of goods received is called the average. To obtain an average sample, small amounts of product (outputs) are taken from different places of several packaging units, mixed and a sample is taken. When sampling from a liquid, it is thoroughly mixed or excavations are taken from different depths; samples of fine-grained and bulk products, cow's butter, cheeses, ice cream are taken with special probes.
The value of the average sample for each product is set by the standards. If, during the organoleptic assessment at the enterprise, the quality of the product is recognized as meeting the requirements of the standards, then the average sample is returned to the place where it was taken from, and, if necessary, sent to the laboratory for analysis by physical, chemical and other indicators. An average sample is taken from the average sample, which is carefully packed, sealed or sealed. Samples are accompanied by an act and a label indicating the name of the enterprise that produces the product, the name, grade and date of production of the product, the batch number from which the sample was taken, the date of sampling, the positions and names of the persons who took the sample, indicators that must be determined in product, the number of GOST, OST, PCT for this product, the number of the transport document Merchandising: Textbook for universities / Ed. G.B. Pole. - M.: UNITI, 2011.- P.123.
Organoleptic methods determine the quality of products using the senses - smell, touch, taste, sight and hearing.
Before organoleptic examination of products, their packaging, labeling, and appearance are checked. Organoleptic methods allow you to establish the quality of the product in terms of shape, color, surface condition, taste, smell, texture. The determination of these indicators requires the necessary skills, knowledge and extensive practical experience, especially when assessing the taste and smell (tasting) of products. The tasting is held in a bright room with completely clean, odor-free air. Room temperature should be between 15-20°C. Before each taste test, rinse your mouth with clean water or chew a piece of bread that adsorbs flavoring substances remaining in the mouth from the previous test. The sample is not swallowed, but only kept in the mouth until the taste is determined. When tasting wines, special pear-shaped glasses are used; when tasting tea, porcelain cups and teapots are used.
For a more objective organoleptic assessment of the quality of cow butter, hard rennet cheeses and some other products, a 100-point system is used, in which 45-50 points are assigned to taste and smell, and depending on the deficiencies found, appropriate discounts are made from the total number of points and according to the sum of points, the grade of the product and its compliance with the requirements of the standard are judged.
Most of the current scoring systems have shortcomings: in different systems, the same indicator is evaluated by a different number of points; some indicators (appearance, packaging, etc.) appear in some systems, but not in others.
Each considered criterion of a competitive bid or indicator that characterizes the qualifications of a supplier receives an assessment in points on a ten-point scale. For this purpose, the values of the analyzed criterion (indicator) in physical units are ranked for all suppliers. The worst value of the criterion (indicator) is assigned one point, the best - ten points. The use of the interpolation method in the range of 1-10 points allows you to determine the score value of the criterion (indicator) for each type of product.
For some products (wine, tea), organoleptic evaluation is so far the only way to determine their quality and variety. However, the organoleptic quality assessment system does not take into account the nutritional value of the product. Therefore, to identify the nutritional value and safety of the product, the organoleptic study is supplemented by physicochemical and microbiological studies.
Physical methods determine the density, melting point, solidification and boiling point, optical properties, etc.
The density of liquids is determined by a hydrometer or pycnometer; by density, for example, the amount of alcohol in alcoholic beverages, the content of acetic acid, sugar and salt in solutions, the nature of vegetable oil, etc. are established. On some hydrometers (alcohol meters), graduation is made by the percentage of alcohol. Ed. M.V. Romanovsky. and O.V. Vrublevskaya.- M.: Yurait, 2011.-p.137.
Melting, freezing and boiling points are determined with a thermometer.
The concentration of water-soluble sugars and salts, as well as the naturalness and purity of oils and fats, is determined refractometrically by the angle of refraction of a beam of light passed through a thin layer of the test substance, which is enclosed between the refractometer prisms.
To determine the type of sugar and its concentration in a solution, a polarimetric method is used - determining the deviation of a polarized beam that has passed through special prisms and through a solution.
The luminescent method is based on the ability of many substances, after illumination with ultraviolet rays, to emit visible light of various shades in the dark. Since fats, proteins and carbohydrates give a luminescent glow of various colors, changing the composition of the product will correspondingly change the intensity of the glow and color.
The ratio of parts in canned food, the amount of filling in caramel, the amount of impurities in cereals, the weight of piece bread, cakes, ice cream, curds and other products are determined by weighing.
Chemical methods establish compliance with the requirements of standards for the content of water, fat, sugar, salt, ash, alcohol, acids in food products. Deviations in the content of the ingredients of products affect their nutritional value, taste and shelf life.
Humidity is determined by drying, electric moisture meters and other methods. The fat content is determined by the volumetric method in butyrometers after dissolving other constituents of the product in strong acids, followed by distillation of the solvent and weighing the fat. The amount of sodium chloride is determined by titration of the aqueous extract from the product with a solution of silver nitrate. The ash content is determined by burning a certain sample of the product in muffle furnaces. The alcohol content in the products is determined by distilling it from the solution and establishing the percentage of alcohol by its density. Acidity is determined by titrating solutions or aqueous extracts of the product with 0.1 N alkali, as well as using a pH meter.
Microbiological methods for studying the quality of food products are used to establish the total bacterial contamination, the presence of pathogenic, putrefactive and other microbes that are harmful to the human body and accelerate the spoilage of products during storage. Such studies are carried out by food laboratories of sanitary and epidemiological stations that supervise the sanitary condition of food enterprises, trade and public catering enterprises. Textbook for training specialists in customs clearance / D.A. Kirillova, D.V. Mikhailov, R.Ya. Supyan. St. Petersburg: European House, 2012.-p.56.
For nutrition, a person consumes food products of plant, animal and mineral origin, which have a certain usefulness, nutritional value, and digestibility. The usefulness of products is determined primarily by their ability to satisfy human nutritional needs. It depends on the chemical composition and characteristics of the transformations of various substances of these products in the human body and is characterized by such basic consumer properties as nutritional, biological, energy and physiological values.
The nutritional value- a complex of substances that determine their biological and energy value. The nutritional value characterizes the fullness of the useful properties of the product, i.e. good quality (harmlessness), digestibility, content of nutrients (proteins, fats, carbohydrates) and biologically active substances (vitamins, minerals, essential amino acids, etc.).
The nutritional value of products is not the same. The highest nutritional value is possessed by products containing proteins, fats, carbohydrates and biologically active substances in the ratio necessary for the human body. Such products are meat, fish, eggs, fish roe, dairy products, etc. At the same time, a number of products have a reduced nutritional value, since they do not have a complete set of essential substances. Individual products are almost entirely composed of one of some compounds. For example, sugar, starch, molasses contain mainly carbohydrates; according to the content of proteins, meat, fish, grain products, cheese are distinguished; there is a lot of fat in butter, lard, sausages; fruits, vegetables and mushrooms contain large amounts of water.
Products must not have harmful effects on human health. Such an influence is possible if they contain harmful compounds (mercury, lead, etc.), pathogenic microbes (Salmonella, botulinum, etc.), impurities (glass, metal), seeds of poisonous plants, etc.
The energy value products is determined by their content of fats, proteins, carbohydrates and their digestibility. The energy value of the product is measured in kilocalories (kcal) or kilojoules (kJ) per 100 g. product. When oxidized in the body, 1 g of fat releases energy equal to 9 kcal (37.7 kJ), 1 g of protein - 4 (16.7 kJ) and 1 g of carbohydrates - 4 kcal (16.7 kJ).
biological value characterized by the presence of biologically active substances in products: vitamins, macro- and microelements, essential amino acids and polyunsaturated fatty acids. The biological value of food reflects, first of all, the quality of the protein component of food, associated with the balance of its amino acid composition, as well as its ability to be digested, assimilated and used by the body as much as possible. These food substances are not synthesized in the body and therefore cannot be replaced by other food substances.
Physiological value - the effect of substances contained in products on the nervous system, cardiovascular, digestive, on the body's resistance to infectious diseases. Tea, coffee, spices and other products have this ability.
Organoleptic value - it affects the human senses, stimulates or suppresses appetite.
Digestibility - is expressed by the digestibility coefficient, i.e. what part of the product is absorbed by the body. Food digested, absorbed into the blood and used for plastic processes, energy restoration is called assimilated. Digestibility depends both on the objective properties of the product (type, taste, aroma, texture, amount of nutrients, etc.), and on the state of the body, nutritional conditions, habits, tastes, etc. The average digestibility of products is (in%): proteins - 84.5, fat - 94 and carbohydrates - 95.6. Food is never 100% digested. Digestibility of food of animal origin 90%, vegetable 90%, mixed 85%. The food boiled, pureed is acquired better.
Food products are different in chemical composition, digestibility, the nature of the impact on the human body.
Carbohydrates are a source of energy, the consumption rate is 400 grams per day (1g - 4 kcal.) Carbohydrates are found in plant products. They are divided into: monosochorides (glucose, fructose), disaccharides (sucrose, lactose, maltose), polysaccharides (starch, fiber is not digested by the body due to the lack of enzymes. It does not release energy, but removes cholesterol and creates conditions for the microflora of the body.)
Fats - a source of energy (1gr - 9 kcal), it is part of the cells and tissues, affects the taste and juiciness of the product. Excess fat is stored as a reserve substance. With a lack of fat, the protective properties of the body are weakened by disorders of the nervous system, growth slows down and protein synthesis decreases. Fat is made up of glycerol and fatty acids. Fatty acids are divided into saturated and unsaturated. Saturated ones have a low biological value, are easily synthesized in the body, and negatively affect fat metabolism. Promotes the development of atherosclerosis. Unsaturated - oleic, lenoleic and orachidonic. According to their biological properties, they are vital. They increase the elasticity of blood vessels, prevent blockage, thrombus, take part in fat metabolism.
Protein is a complex organic compound made up of amino acids. It is the main plastic material for the body. They form the basis of hormones, enzymes, antibodies. Proteins contribute to normal metabolism and release energy (1g - 4 kcal). With a lack of protein, there may be a slowdown in the growth and development of children, a change in the liver, in the composition of the blood, a weakening of the mental and resistance to infections. Mainly found in animal products. The daily norm of proteins and fats is 80 - 100 grams. Table 1 shows the average values for each class of substances. Exact values may vary slightly from substance to substance.
Table 1 - Energy value of the main components of food
At the same time, it should be borne in mind that ensuring normal life is possible only with a balanced diet, when the proportions of individual food components are determined, taking into account the need for energy and building materials, as well as essential food components that are not synthesized in the human body.
To maintain the high vital potential of the human body, it is necessary, first of all, to take care of high-quality food products.
Food quality- a set of properties that reflect the ability of the product to provide organoleptic characteristics, the body's need for nutrients, its safety for health, reliability during manufacture and storage.
Food products are complex multicomponent systems consisting of hundreds of chemical compounds, each of which can have a positive or negative effect on the human body and its health. All these compounds can be conditionally divided into three groups:
1.Compounds of nutritional value- These are the nutrients necessary for the body: proteins, fats, carbohydrates, vitamins, minerals.
Proteins are vital substances. They have a plastic meaning: they serve as a material for building cells, tissues, organs, the formation of enzymes and most hormones, hemoglobin and other compounds. Proteins are an indispensable part of food, as they do not accumulate in reserve and are not formed from other nutrients. Protein deficiency leads to a deterioration in the functions of the digestive, endocrine, hematopoietic and other body systems, muscle atrophy. Efficiency is weakened, resistance to infections decreases, recovery from various diseases slows down. An excess of protein leads to an overload of the liver and kidneys with its decay products, an increase in putrefactive processes in the intestines, and an accumulation of nitrogen metabolism products in the body.
Fats - are part of cells and cellular structures, participate in metabolic processes. Excessive fat intake contributes to the development of atherosclerosis and ischemic heart disease, obesity, cholelithiasis, etc. The lack of some essential fatty acids and lecithin also has a harmful effect on the body - the digestion process is disrupted, the transport of fats into the blood is disrupted, fat metabolism is disrupted, etc.
Carbohydrates - make up the bulk of the human diet and are necessary for the normal metabolism of proteins and fats. The lack of carbohydrates leads to a violation of the metabolism of fats and proteins, the consumption of food proteins and tissue proteins. Harmful products of incomplete oxidation of fatty acids and some amino acids accumulate in the blood. An excess of carbohydrates contributes to the development of obesity, diabetes, and impaired fat metabolism.
Vitamins are biologically active substances that regulate metabolism and affect the vital activity of the body in many ways. Vitamins act on metabolism independently as part of enzymes. Vitamins are not formed in the human body, so they are essential nutrients. With a lack of vitamins in the body, hypovitaminosis occurs (a decrease in the body's supply of one or more vitamins) and vitamin deficiency (complete depletion of vitamin reserves in the body).
Minerals - micro and macro elements. Macronutrients include calcium, phosphorus, magnesium, potassium, sodium, chloride and sulfur. Trace elements - iron, copper, manganese, zinc, cobalt, iodine, fluorine, chromium, molybdenum, vanadium, nickel, strontium, silicon, selenium. Minerals are involved in the construction of body tissues, especially bones.
2.Substances involved in the formation of taste, aroma, color.
3.Foreign, potentially dangerous compounds.
Important characteristics of food that also affect the quality are:
1. The nutritional value - a concept that reflects the fullness of the useful properties of a food product, including the degree to which a person's physiological needs for basic nutrients are met, energy and organoleptic qualities. It is characterized by the chemical composition of the food product, taking into account its consumption in generally accepted quantities.
2. biological value - an indicator of the quality of food protein, reflecting the degree to which its amino acid composition corresponds to the body's needs for amino acids for protein synthesis.
3. The energy value - the amount of energy in kilocalories released from a food product in the human body to ensure its physiological functions.
The energy value of food products is characterized by a balance.
Negative energy balance - when the calorie content of the diet does not cover the energy costs produced by a person. At the same time, food (alimentary) dystrophy, insanity, etc. develop.
Positive energy balance - when the calorie content of the diet for a long time significantly exceeds the energy costs of the human body. At the same time, diseases such as obesity, atherosclerosis, hypertension, etc. develop.
The human body uses the energy it receives from food in three ways:
1. BX- the minimum amount of energy needed by a person to ensure vital processes in a state of complete rest. It is customary to rely on the “standard” man (age 30, weight 65 kg) and woman (age 30, weight 55 kg) for the main exchange. In a standard man, the main metabolism averages 1600 kcal per day, in a woman - 1400 kcal. The basic metabolism significantly depends on age, individual characteristics of the organism, living conditions and labor activity. In people who constantly experience physical activity, the basal metabolic rate is 30% higher. The main metabolism is calculated per 1 kg of body weight, taking into account the fact that 1 kilocalorie is consumed in 1 hour.
2. Energy consumption for food recycling processes. For the breakdown of nutrients in the body, a certain amount of energy is spent in the form of ATP. Digestion of proteins increases basal metabolism by 30-40%, fats - by 4-14%, carbohydrates - by 4-7%.
3. Energy expenditure for muscle activity. With different types of physical activity, energy consumption is different: for people who do not have physical activity, it is 90-100 kcal/hour, while playing sports - 500-600 kcal/hour and more.
If we summarize these data, then the average daily energy consumption for mental workers will be: men - 2550-2800 kcal, women - 2200-2400, workers engaged in physical hard work - 3900-4300 kcal.
At the same time, both the deficiency and excess of food calories affect the health of people. If the daily calorie content of food exceeds energy consumption by 300 calories (1 bun 100 g), then the accumulation of reserve fat can increase by 15-30 g per day and amount to 5-10 kg per year.
In addition to the above characteristics of foodstuffs, care must be taken to ensure that foodstuffs are not contaminated with foreign substances.
The main ways of contamination of food and food raw materials can be varied, the main ones are:
1. Use of unauthorized dyes, preservatives, antioxidants, or their use in high doses.
2. The use of new non-traditional technologies for the production of food products or individual nutrients, including those obtained by chemical and microbiological synthesis.
3. Contamination of crops and livestock products with pesticides used to control plant and animal pests.
4. Violation of hygienic rules for the use of fertilizers, irrigation water, solid and liquid waste from industry and animal husbandry, municipal and other waste water in crop production.
5. Use of unauthorized preparations in livestock and poultry farming.
6. Migration of toxic substances into food products from food equipment, utensils, inventory, containers, packaging, etc.
7. Formation of endogenous toxic compounds in food products during heat treatment.
8. Failure to comply with sanitary requirements for the technology of production and storage of food products, which leads to the formation of toxins.
9. Entry into food of toxic substances, including radionuclides from the environment.
With an even distribution of food products, their production would be sufficient to meet 94% of all energy needs of the world's population. This confirms that at the present level of development, the needs of mankind in food calories can be fully satisfied. The modern world is characterized by a discrepancy between the growth in the population of individual countries and the increase in food production in them.
Estimating the number of people eating less than what they need is complicated by the lack of a unified view of how many calories a person needs. For example, people living in warm climates may need fewer calories. Even within the same region, calorie requirements seem to vary from person to person by up to 50%. Another problem is that nutrition estimates based on indicators for developed countries may be too high, since people in these countries are considered to be overeating. In addition, there is a tendency to count only those crops that pass through the market, such as cereals, or those animals that are easy to count, such as cattle. This method is likely to underestimate food intake, at least in rural areas where there are still other sources of food, such as private households.
According to another approach, food stocks in the region are divided by the number of people living there. This method does not take into account the fact that incomes are unevenly distributed among people, as a result of which the purchasing power of people is also different.
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