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Chemical preservation


In our country, a limited number of chemicals are used for canning. Their use is allowed only in cases where other methods of conservation are ineffective.
Three groups of chemicals are allowed for use: antiseptics, antibiotics, antioxidants.
Preservation with antiseptics. At present, benzoic, sulfuric, boric, sorbic acids and their compounds are used for canning products in industrial conditions.
There are a number of requirements for antiseptics, they should not:
have a toxic effect on the human body in authorized doses; inhibit the action of enzymes of the gastrointestinal tract;
destroy vitamins contained in foods; change the organoleptic and physico-chemical properties of products;
accumulate (cumulate) in the human body.
For each of the used antiseptics, a laboratory methodology for determining them in food should be developed.
Benzoic acid is used (at the rate of 70-100 mg / kg of product) in the production of melange, fruit and berry semi-finished products, in the manufacture of marmalade and marmalade, fruit juices, caviar, canned fish. Benzoic acid does not have pronounced antiseptic properties, its effect is manifested only in an acidic environment. The natural content of benzoic acid in lingonberries and cranberries (500-2000 mg / kg) ensures their long-term preservation.
Sulfuric acid is used to preserve vegetables, fruits, berries, a process called sulfitation. In the industrial preparation of products, sulfuric acid compounds are used - sodium pyrosulfite, sulfur dioxide, sulfur dioxide and sodium bisulfite. In public catering enterprises, sodium bisulfite is used to sulfate potatoes. Sulfuric acid and its compounds destroy vitamin Bi (thiamine), therefore, it is not used for preserving products containing thiamine. Significant destruction (up to 70%) of sulfuric acid preparations occurs during the heat treatment of products. Due to changes in the organoleptic properties of meat, fish, egg and dairy products, their conservation with the help of sulfuric acid and its compounds is not allowed.
Sorbic acid is used in the food industry relatively recently. Its negative effect on the human body and the properties of the products are not marked. Sorbic acid is used in a concentration of 0.1% for the preservation of juices, berries, apples, granular caviar, in the preparation of mayonnaise, soft drinks, cheeses.
Boric acid and sodium borate (borax) are used for conservation purposes in a limited way, since they cause impaired renal and intestinal function and have the ability to accumulate in the body.
Boric acid is currently approved for the production of salmon caviar and melange.
Preservation with antibiotics. In order to maintain the quality of certain food products (meat, fish, poultry), to inhibit the growth of microorganisms, antibiotics are used. The following requirements are imposed on antibiotics: they must not change the organoleptic properties of the products, be stable in the environment and during the heat treatment of products.
Antibiotics are of limited use, as they can cause the variability of microbes and the appearance of antibiotic-resistant forms.
To preserve the quality of meat in carcasses of carcasses and fish during their transportation, biomycin ice is used (5 g of the preparation per 1 ton of ice), with which meat and fish are transferred, and the residual content of biomycin in the raw product is normalized to not more than 0.25 mg / kg. After heat treatment, the antibiotic content in the product is not allowed.
To prevent the development of mold and yeast during transportation and storage of meat carcasses, the use of a combined solution of biomycin is allowed
and nystatin. The solution is applied by irrigating the surface of the carcasses. The concentration of the solution is strictly standardized.
For the preservation of vegetables (green peas, tomatoes, cauliflower, etc.), in the production of cheeses, canned milk, nisin is used. Nisin inhibits the growth of staphylococci, streptococci, spore-forming bacteria. Staphylococci and Cl are especially sensitive to nisin. perfringens. Mildew and yeast are resistant to lowlands. By acting on spores of heat-resistant bacteria, nisin weakens their resistance to heat. This allows you to reduce the sterilization temperature of canned food, thereby preserving the biological value of the products to a greater extent.
Once in the human body, nisin is rapidly destroyed in the digestive tract, without adversely affecting the beneficial intestinal microflora.
The use of antioxidants. Antioxidants are chemical compounds that prevent the oxidation of fats, i.e., prevent their deterioration.
To maintain the quality of fats during storage, it is necessary to create favorable conditions - to exclude the effects of light, heat, oxygen, moisture. The spoilage of fats intended for storage for more than three months is also hindered by the use of antioxidants.
One of the antioxidants is ascorbic acid and its salts, which, in addition, increase the nutritional value of fats in vitamin terms.
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Chemical preservation

  1. The effect of antimicrobial chemicals on microorganisms
    In addition to nutrient chemicals that have a positive effect on microorganisms, there are a number of chemicals that inhibit or completely stop their growth. Chemicals cause either microbicidal (death of microorganisms) or microbostatic effect (they stop their growth, but after removal of this substance, growth resumes again). Nature of action (microbicidal
  2. Alien chemicals in food
    Foreign chemical substances (CHV) include compounds that, by their nature and quantity, are not inherent in a natural product, but can be added to improve technology, maintain or improve the quality of the product and its nutritional properties, or they may form in the product as a result of technological processing (heating, frying, irradiation, etc.) and storage, as well as
  3. CLASSIFICATION OF CHEMICALS (ELEMENTS) BY THEIR TOXICITY
    All substances that adversely affect beneficial animals and humans are divided into groups according to the degree of their acute or chronic toxicity, the level of functional or material cumulation, and chemical affiliation. Criteria of toxicity of substances. The toxicity of chemicals is usually characterized by the following criteria: LD5o (SK5o), LD (SK)) 6, LD (SK) 84, maximum
  4. Carcinogenic chemicals in food
    One of the oldest medical problems is Nutrition and Cancer. This is because food may contain carcinogenic chemicals (CCC) and their precursors. KHV sources primarily include waste from industrial enterprises, thermal power plants, heating systems and vehicles. Migrating in the atmosphere, in soil and in water bodies, these carcinogens can enter food products. Of such
  5. Food contamination with foreign chemicals
    Alien chemical substances (ChW) are also called xenobiotics (from the Greek. Xenos - alien). They include compounds which, by their nature and quantity, are not inherent in a natural product, but can be added to improve technology, preserve or improve the quality of the product, or they may form in the product as a result of processing and storage, as well as
  6. Prevention measures for industrial pollution by harmful chemicals
    The basis of preventive measures (see Chapter 10) is the integrated application of legislative, technological, hygienic and medical and preventive measures. We single out hygienic and medical and preventive measures: recording and investigating the causes of occupational poisoning; preliminary and periodic medical examinations of employees; sanitary instruction; use of measures
  7. Therapeutic tactics in emergency situations with exposure to chemical poisonous substances (AHOV)
    Currently, tens of thousands of various chemicals are used in industry and agriculture. Some of them are toxic and harmful. Any emergency situations - leakage, pipeline breakdown, tank destruction, fire, explosion - can lead to the release of a large amount of chemical poisonous substances into the atmosphere and the earth. According to the degree of toxicity, these substances are divided into
  8. Chemical poisoning
    This group of non-microbial food poisoning includes poisoning caused by pesticides, nitrites and other food additives when their content is high in food products, impurities transferred to products from equipment, inventory, containers, packaging films, etc. Poisoning with nitrites and other food additives when they are increased content in products Nitrite poisoning. With constant
  9. Acute pulmonary edema caused by chemicals, gases, fumes and vapors of increased permeability of the alveolocapillary membrane (inhalation of aggressive fluids, anaphylaxis)
    ICD-10 code J68.1 Diagnosis Diagnosis Mandatory Level of consciousness, respiratory rate and effectiveness, heart rate, pulse, blood pressure, ECG R-graph of chest organs Laboratory tests: hemoglobin, blood gases, KOS, electrolytes (K, Na, Mg, Ca, Cl), blood glucose, white blood cells, blood count, enzymes (CPK), urea, creatinine Additional (according to indications) ultrasound
  10. CHEMICAL COMPOSITION OF A CELL AND ITS PHYSICAL AND CHEMICAL PROPERTIES
    The elemental composition of the cell (protoplasm). To clearly imagine the biological and physicochemical properties of tissues, it is necessary to know the chemical composition of the protoplasm of the cell. In addition to water, there are a large number of elements in the protoplasm. The finest chemical studies have found that out of 104 elements of the periodic system of D. I. Mendeleev, protoplasm contains 96. Four
  11. Purpose and classification of canning
    Preservation is a reliable way to preserve the biological value, taste and epidemiological safety of food for a long time. The use of canning reduces the effect of seasonality in the use of products, especially fruits, berries, vegetables and their processed products. Canned foods can be transported over long distances, which gives
  12. The chemical composition of water. Water pollution: physical, chemical, bacteriological. Self-cleaning ability of water sources
    The chemical composition of water. In nature, water almost always contains more or less mineral salts dissolved in it. The degree and mineral composition of water is determined by the nature of the soil or soils adjacent to aquifers or surface water sources. The amount of mineral salts contained in the water is expressed in mg / L. Organic matter Of these, the most important
  13. Blood preservation
    Basic concepts Blood preservation is a set of effects on it, aimed at creating conditions for long-term storage of blood outside the body in a sterile state with the maximum preservation of its biological properties (both uniform elements and the liquid part of the blood). Two methods are used for blood preservation: canning at positive temperatures;
  14. CANNED SALT MEAT CANNING
    General characteristics of the method. The meat ambassador as a method of conservation has been used since ancient times. Salted meat is called corned beef. Corned beef can be stored at positive temperature for a long time. However, this conservation method has a number of serious disadvantages. The main one is the reduction in the nutritional benefits of meat. In the process of salting and storage, meat loses significant
  15. Preservation by changing environmental properties
    Preservation of food products by changing the properties of the environment aims to change the chemical properties of the product to a level at which the growth and reproduction of microorganisms becomes impossible. Preservation by increasing the osmotic pressure Preservation by increasing the osmotic pressure can be carried out by the methods of salting the product and using sugar. In a microbial cell for her
  16. Combined Preservation Methods
    Combined canning methods include smoking and preserving. Smoking. Smoking is a method of preserving fish, sausages, cheese. In addition to the preserving effect, when smoked, the taste and aromatic properties of products increase. Smoking is a combined exposure of a product to elevated temperature, table salt, drying, smoke, or
  17. NEW CANNING METHODS
    New methods of conservation include freeze-drying, ionizing and infrared irradiation, microwave, as well as electrical contact heating. Freeze-drying. When freeze-drying, the product is dehydrated in a frozen form under vacuum. In this case, ice (frozen moisture of meat) passes into a vapor state bypassing the liquid phase. Drying is carried out in special
  18. Dehydration preservation
    Preservation by dehydration in natural conditions has been used since ancient times to preserve products for a long time. When dried in the product, the amount of moisture decreases (up to 15% and below). The development of most microorganisms stops when the humidity of the product is below 30%. The timing of the death of microbes in the dehydrated product is different: the cholera vibrio remains viable for 2 days,
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