General provisions

METHODS OF PROTECTION
FOOD PRODUCTS AGAINST SPOILAGE

CAUSES OF FOOD SPOILAGE

As you know, food products of plant and animal origin cannot be kept fresh for long. The reason for their spoilage is the activity of microorganisms and enzymes.

Bacteria are the most significant group of single-celled organisms of various types and shapes. They reproduce by cell division. Most of them are harmful, causing illness in the body and food spoilage.
The exception is lactic acid bacteria, which are widely used in the production of lactic acid products, fermentation, pickling and other processing of food raw materials.

Yeasts are single-celled organisms of oval, oblong or round shape. Yeast reproduces by division and budding, and under favorable conditions also by spores.
Yeast is also used in home canning. Under their influence, sugar, in the absence of air, decomposes into alcohol and carbon dioxide, due to which known types of yeast are used to make wine, beer, kvass and other drinks.
Some types of yeast cause food spoilage and rancidity during storage.
A high content of salt or sugar in products stops the action of yeast, which is also used when salting fish, meat, making jam, etc.

Molds (mold fungi) have a complex structure in the form of mycelium that forms on the surface of food products. As the mycelium develops, it produces a large number of spores that are easily carried by the wind. It reproduces not only by spores, but also by division, especially well with access to oxygen and moisture.
Accumulations of mold are clearly visible (for example, green and gray-black on bread, fruits and vegetables, white on sauerkraut).

For all types of microorganisms, there are certain temperature limits within which they can live and develop normally.

For most of them, the best temperature is between 20 and 40°C.

From 0°C and below, it does not kill microorganisms, but only suspends their vital activity.

At temperatures above 60-100°C, most bacteria die, and only a few species can withstand temperatures of 100-120°C.

In favorable conditions, microorganisms multiply very quickly. It only takes a little time for a few microbes to turn into millions of living cells.

In the course of their life activity, certain types of microorganisms can produce potent toxic substances (toxins). That is why you should not eat raw materials and finished products of questionable quality.

Each type of microorganism feeds on certain substances that are soluble in water. They cannot exist without water.

There are microorganisms that require air oxygen to function (aerobic), and those that can do without it (anaerobic).

Fruits, vegetables and other food products of plant and animal origin with a high acid content are an unfavorable environment for the development of bacteria, and yeasts and molds multiply well in an acidic environment.

To destroy mold fungi, it is enough to heat the food product at 100°C (i.e. at the boiling point of water) for 1-2 minutes or heat it at 85°C for 5-6 minutes.

In foods with low or no acidity, in addition to molds and yeasts, other types of microorganisms can grow. In this case, heating at 85°C or boiling at 100°C will be insufficient; exposure to higher temperatures of the order of 112-120°C will be required.
Therefore, raw materials with natural acidity are recommended for home canning. Otherwise, food acids (citric, tartaric, acetic, etc.) should be added to low-acid raw materials or mixed with other types of raw materials of high natural acidity.

WAYS TO PROTECT FOOD PRODUCTS FROM SPOILAGE

In an effort to protect food products from spoilage, in ancient times man developed a method of preserving them (canning) by drying, smoking, salting and fermenting, pickling, and subsequently cooling and freezing, preserving with sugar or using preservatives and heat treatment.

Let's consider these methods.

Drying. The preservative effect of drying food products is to remove moisture. When dried, the dry matter content of the product increases, which creates unfavorable conditions for the development of microorganisms.
Increased humidity in the room and air can cause deterioration of dried products - the appearance of mold. Therefore, they must be packaged in containers that exclude the possibility of increasing moisture in the product.

Smoking. This method is used for preparing meat and fish products. It is based on the preservative effect of some components of flue gases, which are obtained during the slow combustion of firewood and hardwood sawdust.
The resulting sublimation products (phenols, creosote, formaldehyde and acetic acid) have preservative properties and give smoked meats a specific taste and aroma.
The preservative effect of smoking substances is enhanced by preliminary salting, as well as partial removal of moisture during salting and cold smoking.

Salting. The preservative effect of table salt is based on the fact that at a concentration of 10 percent or more, the vital activity of most microorganisms ceases.
This method is used for salting fish, meat and other products.

Pickling. When fermenting food products, mainly cabbage, cucumbers, tomatoes, watermelons, apples and others, biochemical processes occur in these products. As a result of lactic acid fermentation of sugars, lactic acid is formed, as it accumulates, conditions for the development of microorganisms become unfavorable.
The salt added during fermentation is not decisive, but only helps to improve the quality of the product.
To avoid the development of mold and putrefactive microbes, pickled products should be stored at low temperatures in a basement, cellar, or icebox.

Pickling. The preservative effect of pickling food products is based on creating unfavorable conditions for the development of microorganisms by immersing them in a solution of food acid.
Acetic acid is usually used for pickling foods.

Cooling. The preservative effect of cooling is based on the fact that at a temperature of 0°C most microorganisms cannot develop.
The shelf life of food products at 0°C, depending on the type of product and the relative humidity in the storage area, ranges from several days to several months.

Freezing. The basis for this storage method is the same as for refrigeration. Prepared products are quickly frozen to a temperature of minus 18-20°C, after which they are stored at a temperature of minus 18°C.
Complete freezing of the product occurs at a temperature of minus 28°C. This temperature is used for industrial storage, but in most cases it is not available at home.
When frozen, the vital activity of microorganisms stops, but when thawed they remain viable.

Canning with sugar. High concentrations of sugar in products of the order of 65-67 percent create unfavorable conditions for the life of microorganisms.
When the sugar concentration decreases, favorable conditions are again created for their development, and consequently, spoilage of the product.

Canning using preservatives. Antiseptics are chemical substances that have antiseptic and preservative properties. They inhibit the processes of fermentation and rotting and, therefore, contribute to the preservation of food products.
These include: sodium benzoate, sodium salicylic acid, aspirin (acetylsalicylic acid). However, it is not recommended to use them at home, since this method of preservation degrades the quality of the products. In addition, these substances are unacceptable in a regular diet.

Heat preservation. Canning, i.e. preserving food products from spoilage for a long time, is also possible by boiling them in a hermetically sealed container.
The food product to be preserved is placed in a tin or glass container, which is then hermetically sealed and heated for a certain time at a temperature of 100°C or higher or heated at 85°C.
As a result of heating (sterilization) or heating (pasteurization), microorganisms (molds, yeasts and bacteria) die and enzymes are destroyed.
Thus, the main purpose of heat treatment of food products in hermetically sealed containers is to sterilize microorganisms.
Food products in hermetically sealed containers do not undergo changes during the sterilization process. With other methods of canning (salting, drying, etc.), products lose their appearance and their nutritional value decreases.

General provisions

STERILIZATION AND PASTEURIZATION

Sterilization is the main way to preserve a food product without significantly changing its taste.

The method of sterilizing canned food in glass containers with immediate sealing with tin lids after boiling is very convenient at home. It provides the necessary tightness and vacuum in the rolled up jar, promotes the preservation of the canned product and its natural color.

Sterilization of products at home is carried out at the boiling point of water. Fruit compotes and vegetable marinades can be sterilized at a water temperature of 85°C (pasteurization). But in this case, pasteurized canned food should be in the sterilizer 2-3 times longer than in boiling water.

In some cases, for example, to sterilize green peas, when the boiling point of water during sterilization should be above 100°C, table salt is added to the water.
In this case, they are guided by the table (indicate the amount of salt in grams per 1 liter of water):

Amount of salt, g/l Boiling point °C
66 ..........................................................101
126..........................................................102
172..........................................................103
216..........................................................104
255..........................................................105
355..........................................................107
378..........................................................110

Canned food prepared at home is sterilized in a pan, bucket or special sterilizer. A wooden or metal grid is placed horizontally on the bottom of the dish. It eliminates the breakage of cans or cylinders during sterilization under sudden temperature fluctuations. You should not place rags or paper on the bottom of the sterilizer, as this makes it difficult to observe when the water begins to boil and leads to product rejection due to insufficient heating.

So much water is poured into the pan to cover the shoulders of the jars, that is, 1.5-2 cm below the top of their necks.

The temperature of the water in the pan before loading filled cans should be at least 30 and no more than 70 ° C and depends on the temperature of the canned food being loaded: the higher it is, the higher the initial temperature of the water in the sterilizer. The pan with the jars placed in it is placed on intense heat, covered with a lid and brought to a boil, which should not be violent during sterilization.

The time for sterilization of canned food is counted from the moment the water boils.

The heat source at the first stage of sterilization, that is, when heating the water and the contents of the jars, must be intense, since this reduces the time of heat treatment of the product, and it turns out to be of higher quality. If we neglect the speed of the first stage, the canned food produced will be overcooked and will have an unsightly appearance. The time for heating water in a saucepan to a boil is set: for cans with a capacity of 0.5 and 1 liter - no more than 15 minutes, for 3-liter jars - no more than 20 minutes.

At the second stage, that is, during the sterilization process itself, the heat source should be weak and only maintain the boiling point of water. The time specified for the second stage of sterilization must be strictly adhered to for all types of canned food.

The duration of the sterilization process depends mainly on the acidity, thickness or liquid state of the product mass. Liquid products are sterilized within 10-15 minutes, thick ones - up to 2 hours or more, acidic products - less time than non-acidic ones, since an acidic environment is not conducive to the development of bacteria.

The time required for sterilization depends on the volume of the container. The larger the container, the longer the boiling takes. It is recommended to write down the start and end times of sterilization on a separate sheet of paper.

At the end of sterilization, the jars are carefully removed from the pan and immediately sealed with a key, checking the quality of the sealing: whether the lid is rolled well, whether it is not turning around the neck of the jar.

Sealed jars or cylinders are placed neck down on a dry towel or paper, separating them from one another, and left in this position until cooled.

Steam sterilization
Canned food is sterilized with steam in the same container where water is boiled for this purpose. The amount of water in the pan should not exceed the height of the wooden or metal grate - 1.5-2 cm, since the less water, the faster it heats up.
When the water boils, the resulting steam warms the jars and the contents in them. To prevent steam from escaping, the sterilizer is tightly closed with a lid.
The time required to bring the water in the sterilizer to a boil is 10-12 minutes.
The time required to sterilize canned food with steam is almost twice as long as when sterilizing in boiling water.

Pasteurization
In cases where it is necessary to sterilize canned food at a temperature below boiling water, for example, for marinades, compotes, they are cooked at a water temperature in a pan of 85-90 ° C. This method is called pasteurization.
When cooking canned food using the pasteurization method, it is necessary to use only fresh, sorted fruits or berries, thoroughly washed from dust; strictly adhere to the temperature and time of pasteurization; Before laying the container, wash it thoroughly and boil it.
The preservation of canned food prepared by pasteurization is facilitated by the presence of high acidity.
You can pasteurize cherries, sour apples, unripe apricots and other sour fruits for preparations and compotes.

Repeated sterilization
Repeated or multiple (two to three times) sterilization of the same jar of food products containing large quantities of protein (meat, poultry and fish) is carried out at the boiling point of water.
The first sterilization kills mold, yeast and microbes. During the 24-hour period after the first sterilization, the spore forms of microorganisms remaining in the canned food germinate into vegetative forms and are destroyed during secondary sterilization. In some cases, canned food, such as meat and fish, is sterilized a third time after a day.
To re-sterilize at home, you must first seal the jars and put special clips or clips on the lids so that the lids do not come off the jars during sterilization.
The clamps or clips are not removed until the cans have completely cooled (after sterilization) to avoid the lids falling off and possible burns.

Sterilization of canned food, previously hermetically sealed
For this method of sterilization, it is necessary to have special metal clips or clips to secure the sealed lids on the jars. This prevents their breakdown during the sterilization process as a result of the expansion of the mass of the canned product, as well as the air remaining in the jar during heating.
The use of special clamps allows you to stack jars in the sterilizer in 2-3 rows.
A vacuum is formed in jars that are hermetically sealed prior to sterilization. It should be remembered that the higher the temperature of the product in the jar at the time of capping, the greater the vacuum obtained.

Hot canning of liquid products without subsequent sterilization
Canning liquid products that have been previously boiled or brought to a boil can be done by hot packaging without subsequent sterilization. Using this method, tomato juice, crushed tomatoes, grape, cherry, apple and other juices, plum preparations for jam, fruit puree from sour fruits, etc. are prepared.
Glass containers - jars and their lids - should be thoroughly washed and steamed in a steam-water bath for 5-10 minutes.
The temperature of the product before filling the jars must be at least 96°C. The jars must be hot when filled with product. Immediately after filling them with the canned product, they are capped.
With this method of canning, sterilization occurs due to the heat transferred to the product and container when they are boiled, and the safety of canned food depends on the quality of the raw materials and its processing.

Hot canning of fruits and vegetables without subsequent sterilization
This method is used for canned vegetables - cucumbers, tomatoes, as well as for fruit preparations and compotes from whole fruits.
For this method of canning, the raw materials must be fresh, thoroughly washed and sorted.
According to this method, canned food is prepared in the following sequence: vegetables or fruits placed in jars are carefully poured with boiling water in 3-4 additions. After pouring in a portion of boiling water, the jar is turned to heat the walls so that the glass does not crack due to sudden temperature fluctuations.
The jars filled with boiling water are covered with a clean lid, wrapped in a towel and kept for 5-6 minutes. Then the water is drained and the jar is again filled with boiling water, covered again with a lid and kept for another 5-6 minutes. If necessary, this operation is repeated a third time.
After the second and third soaking, the water is drained and immediately poured with boiling marinade for cucumbers and tomatoes, boiling water for fruit preparations and boiling syrup for compotes.
Then immediately cover with a lid, seal and check the quality of the seal.
After capping, the jar is placed upside down. Cooling is in air.

General provisions

CONDITIONS, SPICES AND SPICES
FOR CANNING

Seasonings and spices are used in home canning to improve the taste, aroma, and often the color of prepared products. A moderate amount of them has a beneficial effect on the taste of food, and also increases the secretion of digestive juices, thereby promoting better absorption of food.
An excessive dose of spices and herbs can cause serious irritation of the gastric mucosa. Therefore, when using seasonings, herbs and spices, it is recommended to be in moderation.

Table salt is the main seasoning necessary for a healthy body and is most often used when preparing food at home.

Vinegar is also an indispensable component for canning.
The most common types of vinegar are table wine, flavored tarragon, grape, apple, etc.
In most cases, the most successful, which does not impart any additional flavors to the product, is alcohol vinegar.
Most often, synthetic acetic acid (acetic essence) diluted with water is sold under the name “vinegar”.
All types of vinegar labeled "flavored" are synthetic vinegar with some synthetic additives.
Store vinegar in a glass container with a tightly closed lid at a temperature of 5 °C.

Citric acid is odorless, and therefore it is recommended to use it when preparing products whose taste does not match the smell of vinegar: compotes, jellies, etc.

Black and white peppers are the dried seeds of a climbing tropical shrub, collected at various stages of maturity. They differ from each other in color, pungency and sharpness of smell (black is more pungent).
When preparing food, pepper is used both in the form of peas and ground. The latter quickly loses its nutritional qualities during long-term storage, so it is recommended to grind the pepper as needed.
Used for pickling, salting, pickling, etc.

Allspice looks like black pepper and appears as dark brown peas. It has a strong pleasant aroma and relatively little pungency.
Used in various types of home canning.

Red pepper is the fruit of a herbaceous plant that resembles a large pod in appearance. Contains many vitamins, in particular vitamin C, surpassing even lemon in vitamin content.
Depending on the amount of a special substance - capsaicin - which gives red pepper its pungency and pungency, sweet (paprika) and bitter peppers are distinguished.
Paprika is a large, fleshy fruit.
The fruits of bitter pepper have an elongated shape. In terms of its pungency and pungency, it can only be compared with black pepper. Can also be used in powder form.

Bay leaf is the dried leaves of the noble laurel tree, which are highly aromatic. The main purpose of bay leaf is to flavor food without giving it any pungency or bitterness.
Excess bay leaves change the taste of the dish for the worse, giving it a too strong smell.
When cooking, it is added at the end, since with prolonged heat treatment it gives a bitter taste.

Cloves are the dried, unopened flower buds of the clove tree.
Cloves get their specific aroma thanks to the valuable essential oils it contains.
Used for pickling, salting and other types of canning.
It is recommended to add cloves shortly before the end of cooking and in small quantities, since even a small dose of cloves gives the product a pronounced aroma.

Coluria. The smell of coluria is close to the smell of cloves. For home canning, it is used instead of cloves in the form of dried roots ground into powder.

Cinnamon is the peeled and dried bark of the shoots of the cinnamon tree. Used in powder or pieces.
When canning at home, it is used to flavor marinades, jams, compotes, etc.

Saffron is the dried stigmas of crocus flowers and has a specific aroma.
Used as a flavoring and coloring agent.

Nutmeg. Nutmeg seeds, shelled and dried.
It has a very pungent and pungent taste and aroma.

Vanilla and vanilla. The first is the fruit of a tropical orchid, which in appearance resembles a pod with very fragrant small seeds inside. Vanillin is a synthetic powder - a substitute for vanilla.
It is used for canning fruits and berries that have a weak aroma of their own (for example, cherry jam).
Excess vanilla and vanillin gives the product a bitter taste.

Ginger. Tropical nut root, peeled and dried. It is used in crushed form and has a pleasant smell and pungent taste.
It is recommended to store it uncrushed, which allows it to better preserve its aroma.

Dill. Young plants in the rosette phase are used as an aromatic seasoning for salads, soups, meat, fish, mushroom and vegetable dishes.
Adult plants in the seed formation phase are used as the main type of spice for pickling and pickling cucumbers, tomatoes, and sauerkraut.

Mint is quite widely used in home preparations due to its pleasant aroma and refreshing taste.
Mint is added when preparing fish, meat, vegetables, and when making kvass. Can be used both fresh and dried.

Coriander is the dried seeds of the herbaceous plant coriander.
Used in pickling, flavoring vinegar, etc.

Basil has a delicate aroma with various shades.
Used fresh and dried for adding to vegetable marinades.

Tarragon is the dried stems and leaves of the herbaceous plant of the same name.
Used for salting, pickling, etc.

Sterilization is the removal or destruction of all living microorganisms (vegetative and spore forms) inside or on the surface of objects.

Sterilization is carried out by various methods: physical, chemical, mechanical.

The basic requirements for the sterilization process are reflected in industry standard 42-21-2-82 “Sterilization and disinfection of medical devices. Methods, means, regimes."

Physical methods. The most common method of sterilization is exposure to high temperature. At temperatures approaching 100 0 C, most pathogenic bacteria and viruses die. Spores of soil thermophilic bacteria die when boiled for 8.5 hours. Microorganisms trapped in the deep layers of the earth, or covered with coagulated blood, are protected from high temperatures and retain their viability.

When sterilizing by physical methods, high temperatures, pressure, ultraviolet irradiation, etc. are used.

The simplest but most reliable type of sterilization is calcination. It is used for surface sterilization of non-flammable and heat-resistant objects immediately before their use.

Another simple and easily accessible method of sterilization is boiling. This process is carried out in a sterilizer - a rectangular metal box with two handles and a tight-fitting lid. Inside there is a removable metal mesh with handles on the sides, on which the instrument to be sterilized is placed. The main disadvantage of the method is that it does not destroy spores, but only vegetative forms.

When steam sterilization, it is necessary to fulfill certain conditions that guarantee its effectiveness and the preservation of the sterility of products for a certain period. First of all, sterilization of instruments, surgical linen, and dressings should be carried out in packaging. For this purpose, the following are used: sterilization boxes (boxes), double soft packaging made of calico, parchment, moisture-resistant paper (kraft paper), high-density polyethylene.

A mandatory requirement for packaging is tightness. The period for maintaining sterility depends on the type of packaging and is three days for products sterilized in boxes without filters, in double soft packaging made of calico, water-resistant paper bags. In sterilization boxes with filters, the sterility of products is maintained throughout the year.

Dry heat sterilization. The dry heat sterilization process is carried out in a dry heat oven (in a Pasteur oven, etc.) - a metal cabinet with double walls. The cabinet body contains a working chamber, which has shelves for placing items to be processed, and heating elements that serve to uniformly heat the air in the working chamber.

Sterilization modes:

temperature 150 0 C – 2 hours;

temperature 160 0 C – 170 0 C 45 minutes – 1 hour;

temperature 180 0 C – 30 minutes;

temperature 200 0 C – 10-15 minutes.

It must be remembered that at a temperature of 160 0 C paper and cotton wool turn yellow, at a higher temperature they burn (carbonize). The beginning of sterilization is the moment when the temperature in the oven reaches the desired value. After sterilization is completed, the oven is turned off, the device cools down to 50 0 C, after which the sterilized items are removed from it.

Products in an air sterilizer can be sterilized without packaging, but only if they are used immediately after sterilization. Sack paper made in accordance with GOST 2228-81 can be used as packaging; products can be stored in it for at least 3 days.

The air sterilization mode is represented by two temperature values ​​- 160 0 C for 2.5 hours, or 180 0 C for 1 hour.

Flowing steam sterilization. This type of sterilization is carried out in a Koch apparatus or in an autoclave with the lid unscrewed and the outlet valve open. The Koch apparatus is a metal hollow cylinder with a double bottom. The material to be sterilized is not loaded tightly into the chamber of the device in order to ensure maximum contact with the steam. The initial heating of water in the device occurs within 10-15 minutes.

Flowing steam is used to sterilize materials that decompose or deteriorate at temperatures above 100 0 C - nutrient media with carbohydrates, vitamins, carbohydrate solutions, etc.

Sterilization with flowing steam is carried out fractional method– at a temperature not higher than 100 0 C for 20-30 minutes for 3 days. In this case, the vegetative forms of bacteria die, and the spores remain viable and germinate within 24 hours at room temperature. Subsequent heating ensures the death of these vegetative cells emerging from spores between stages of sterilization.

Tyndalization– fractional sterilization method, in which the sterilized material is heated at a temperature of 56-58 0 C for an hour for 5-6 days in a row.

Pasteurization– single heating of the material to 50-65 0 C (for 15-30 minutes), 70-80 0 C (for 5-10 minutes). Used to destroy non-spore forms of microbes in food products (milk, juices, wine, beer).

Pressure steam sterilization. Sterilization is carried out in an autoclave under pressure usually (dishes, saline solution, distilled water, nutrient media that do not contain proteins and carbohydrates, various devices, rubber products) for 20-30 minutes at a temperature of 120-121 0 C (1 atm.) , although other relationships between time and temperature may be used depending on the object being sterilized.

Any solutions containing proteins and carbohydrates are sterilized in an autoclave at 0.5 atm. (115 0 C) for 20-30 minutes

Any material infected with microorganisms (infectious) is sterilized at a pressure of 1.5 atm. (127 0 C) – 1 hour, or at a pressure of 2.0 atm. (132 0 C) – 30 minutes.

When the solutions to be sterilized are in glass vessels, at the end of the sterilization cycle it is necessary to control the cooling time and also slowly reduce the pressure, because The autoclave can only be opened after ambient pressure has been established.

Sterilization by irradiation. Radiation can be non-ionizing (ultraviolet, infrared, ultrasonic, radio frequency) and ionizing - corpuscular (electrons) or electromagnetic (x-rays or gamma rays).

The effectiveness of irradiation depends on the dose received, and the choice of dose is determined by microbial contamination, the shape and composition of the material to be sterilized.

Ultraviolet irradiation (254 nm) has low penetrating power, therefore it requires quite a long exposure and is used mainly for sterilizing air and open surfaces in rooms.

Ionizing radiation, primarily gamma irradiation, is successfully used for sterilization in industrial conditions of medical devices made from thermolabile materials, since they allow materials to be quickly irradiated at the production stage (at any temperature and in sealed packaging). Currently, it is widely used to produce sterile disposable plastic products (syringes, blood transfusion systems, Petri dishes), and surgical dressings and suture materials.

MECHANICAL METHODS. Filters retain microorganisms due to the porous structure of the matrix, but a vacuum or pressure is required to pass the solution through the filter, since the force of surface tension with such a small pore size prevents liquids from being filtered.

There are 2 main types of filters - depth and filtering.

Depth filters consist of fibrous or granular materials (asbestos, porcelain, clay), which are compressed, coiled or connected into a labyrinth of flow channels, so there are no clear pore size parameters. Particles are retained in them as a result of adsorption and mechanical entrapment in the filter matrix, which provides a fairly large filter capacity, but can lead to retention of part of the solution.

Filter filters have a continuous structure, and their particle capture efficiency is determined primarily by their matching to the filter's pore size. Membrane filters have low capacity, but efficiency is independent of flow rate and pressure drop, and little or no filtrate is retained.

Membrane filtration is now widely used for the sterilization of oils, ointments and solutions that are unstable to heat - solutions for intravenous injections, diagnostic drugs, solutions of vitamins and antibiotics, tissue culture media, etc. and so on..

CHEMICAL METHODS. Chemical sterilization methods involving the use of chemicals with pronounced antimicrobial activity are divided into 2 groups: sterilization with gases and solutions (more often known as “disinfection”).

Chemical methods of gas sterilization are used in medical institutions to disinfect medical materials and equipment that cannot be sterilized by other methods (optical instruments, pacemakers, heart-lung machines, endoscopes, polymer products, glass).

Many gases have bactericidal properties (formaldehyde, propylene oxide, ozone, peracetic acid and methyl bromide), but ethylene oxide is most widely used, since it is well compatible with various materials (does not cause corrosion of metal, damage to processed products made of paper, rubber and all types of plastics ). The exposure time when using the gas sterilization method varies from 6 to 18 hours depending on the concentration of the gas mixture and the volume of the special apparatus (container) for this type of sterilization. According to the “Methodological recommendations for disinfection, pre-sterilization cleaning and sterilization of medical instruments” No. 26-613 dated 02/09/88. For sterilization with gases, it is possible to use a microanaerostat as a gas sterilization apparatus, and in addition to ethylene oxide or a mixture of ethylene oxide with methyl bromide, vapors of 40% formaldehyde in ethyl alcohol at a temperature of 80 0 C in a sterilization chamber for 60 minutes.

Sterility control produced in specially equipped boxes that exclude the possibility of secondary contact of products with microflora. At least 1% of simultaneously sterilized products are selected for control. Products are inoculated into a nutrient medium for control. If there is no bacterial growth, a conclusion is made that the product is sterile.

Sterilization with solutions is used when treating large surfaces (spaces) or medical devices that cannot be disinfected by other methods.

According to the requirements of the industry standard OST 42-21-2-85 “Guidelines for disinfection, pre-sterilization cleaning and sterilization of medical products”, most medical products made of metal, glass, plastics, rubber undergo pre-sterilization treatment, consisting of several stages:

– soaking in a washing solution with the product completely immersed in a disinfectant solution for 15 minutes;

– washing each disassembled product in a washing solution manually for 1 minute;

– rinsing well-washed items under running water for 3-10 minutes;

– drying with hot air in a drying cabinet.

Quality control of pre-sterilization cleaning of medical devices for the presence of blood is carried out by performing an amidopyrine test. Residual amounts of alkaline detergent components are determined using a phenolphthalein test.

According to the requirements of the same OST, a mandatory condition for sterilization of medical devices with solutions is the complete immersion of the products in a disassembled sterilization solution, with filling of channels and cavities, at a solution temperature of at least 18°C. Use only enamel containers (without damage) with glass or plastic lids. After sterilization, the products are quickly removed from the solution using tweezers or forceps, the solution is removed from the channels and cavities, then the sterilized products are washed twice successively with sterile water. Sterilized products are used immediately for their intended purpose or placed in a sterile container lined with a sterile sheet and stored for no more than 3 days. In a special journal, mandatory records are kept of all cycles of chemical sterilization, indicating the date, exact time of sterilization (filling, removing the solution), the name of the drug used and its concentration.

Preparations used for sterilization are classified into groups: acids or alkalis, peroxides (6% hydrogen peroxide solution), alcohols (ethyl, isopropyl), aldehydes (formaldehyde, glutaraldehyde), halogens (chlorine, chloramine, iodophors - vescodin), quaternary ammonium bases, phenolic compounds (phenol, cresol).

In addition, universal preparations can be used as convenient and economical disinfectant solutions, i.e. allowing for disinfection from all forms of microorganisms (bacteria, including Mycobacterium tuberculosis, viruses, including HIV, pathogenic fungi) or combination drugs (“Deseffect”, “Alaminal”, “Septodor”, “Virkon”), combining two processes at the same time - disinfection and pre-sterilization treatment.

A set of disinfection measures aimed at removing or destroying pathogens of infectious diseases in objects or on abiotic environmental objects, i.e. when they are transmitted from a source to susceptible people, it is divided into 2 types: focal disinfection and preventive disinfection.

Focal disinfection carried out in epidemic foci and in turn is divided into current, if the source of the pathogen is present, and s final, if the source is deleted.

Current Disinfection is aimed at the constant disinfection of excrement, vomit, sputum, pathological discharge, dressings and other objects in the patient’s environment that are or could be contaminated with pathogens during the entire period while the patient or carrier serves as a source of the infectious agent.

Final disinfection is aimed at destroying pathogenic microorganisms remaining in the outbreak in a viable state on various objects, although the source has been removed, i.e. after hospitalization, recovery or death of the patient. During the final disinfection, premises, excrement, vomit, linen, household items and all other objects that could be contaminated with pathogens of this disease are subject to treatment. This type of disinfection is usually carried out by specialized services of state epidemiological surveillance authorities.

Preventive disinfection carried out if the source of infection has not been detected, but the possibility of its existence is assumed. This type of disinfection is most often used in medical institutions (prevention of occupational infection of medical personnel with nosocomial infections), in catering establishments, enterprises that manufacture, process and sell food products, as well as in crowded places where there may be a source of the causative agent of an infectious disease among healthy population.

For intestinal infections, disinfection measures are aimed at cleaning and disinfecting sources of drinking water supply, wastewater, waste, food products, materials from the patient, dishes, linen, catering units, and bathrooms. Both current and final disinfection are carried out in the outbreak.

For respiratory tract infections, disinfection is carried out in order to reduce microbial air pollution in specific rooms, which can be achieved not only by wet cleaning and disinfection of objects in the patient’s environment, but also by ventilation or UV irradiation of the air in a given room.

In foci of vector-borne infections, disinfection measures are carried out only for plague, tularemia, Q fever, and at facilities where they work with blood.

In case of infections of the external integument, all used items (linen, combs, scissors, sponges) in baths, showers, swimming pools, hairdressers must be disinfected, and it is recommended, if possible, to use universal preparations that have bactericidal (including sporicidal), virucidal , fungicidal properties.

When preventing nosocomial infections, all medical products, personnel hands, wound surfaces, surgical fields, etc. must be disinfected after each patient. and so on.

Biological sterilization - based on the use of antibiotics, used limitedly - in tissue cultures for cultivating viruses.

The main way to preserve a food product without significant changes in its taste is sterilization.

The method of sterilizing canned food in glass containers with immediate sealing with tin lids after boiling is very convenient at home. It provides the necessary tightness and vacuum in the pumped jar, reaching 300-350 mm Hg, and contributes to the preservation of the canned product and its natural color.

Sterilization of canned food at home is carried out at the boiling point of water.

Fruit compotes and vegetable marinades can be sterilized at a water temperature of 85 degrees (pasteurization). But in this case, pasteurized canned food should be in the sterilizer 2-3 times longer than in boiling water. A thermometer is used to determine the water temperature.

In some cases (for example, for sterilizing green peas), when the boiling point of water during sterilization should be above 100 degrees, table salt is added to the water. In this case, they are guided by the following table:

Canned food prepared at home is sterilized in a pan, bucket or in a special sterilizer. A wooden or metal grid is placed horizontally on the bottom of the dish. It eliminates the breakage of cans or cylinders during sterilization under sudden temperature fluctuations. You should not place rags or paper on the bottom of the sterilizer, as this makes it difficult to observe the beginning of the water boiling and leads to defective products due to insufficient heating.

So much water is poured into the pan to cover the shoulders of the jars, that is, 1.5-2.0 cm below the top of their necks.

The temperature of the water in the pan before loading filled cans should be at least 30 and no more than 70 degrees and depends on the temperature of the loaded canned goods: the higher it is, the higher the initial temperature of the water in the sterilizer. The pan with the jars placed in it is placed on intense heat, covered with a lid and brought to a boil, which should not be violent during sterilization.

The time for sterilization of canned food is counted from the moment the water boils.

Rice. 20. Pan adapted for sterilization

The heat source at the first stage of sterilization, that is, when heating the water and the contents of the jars, must be intense, since this reduces the heat treatment time of the product, and it turns out to be of high quality. If we neglect the speed of the first stage, then the canned food produced will be overcooked and will have an unsightly appearance. The time for heating water in a pan to a boil is set: for cans with a capacity of 0.5 and 1.0 liters - no more than 15 minutes, and for 3-liter cylinders - no more than 20 minutes.

At the second stage, that is, during the sterilization process itself, the heat source should be weak and only maintain the boiling point of water. The time specified for the second stage of sterilization must be strictly adhered to for all types of canned food.

The duration of the sterilization process depends mainly on the acidity, thickness or liquid state of the product mass. Liquid products are sterilized within 10-15 minutes, thick ones - up to two or more hours, acidic products - less time than non-acidic ones, since an acidic environment is not conducive to the development of bacteria. The time required for sterilization also depends on the volume of the container. The more, the longer the boiling lasts.

Is the lid sealed well and does it not turn around the neck of the jar?

Rice. 21. Metal grill

Rsi. 22. Sterilization of canned food in a pan

There are special tongs available for removing hot jars from pans. They are very convenient to use.

Sealed jars or cylinders are placed neck down on a dry towel or paper, separating them from one another, and left in this position until cooled.

Steam sterilization of jars

Canned food is sterilized with steam in the same container where water is boiled for this purpose. The amount of water in the pan should not exceed the height of the wooden or metal grate - 1.5-2 cm, since the less water, the faster it heats up.

When the water boils, the resulting steam warms the jars and the contents in them. To prevent steam from escaping, the sterilizer is tightly covered with a lid.

The time required to bring the water in the sterilizer to a boil is 10-12 minutes.

The time required to sterilize canned food with steam is almost twice as long as when sterilizing in boiling water.

Pasteurization of canned food in jars

In cases where it is necessary to sterilize canned food at a temperature below boiling water (for example, for marinades, compotes), they are cooked at a water temperature in the pan of 85-90 degrees. This method is called pasteurization.

When cooking canned food using the pasteurization method, you must:

1. use only fresh, sorted fruits or berries, thoroughly washed from dust;
2. strictly adhere to the temperature and time of pasteurization;
3. Before laying the container, wash it thoroughly and boil it.

To measure the temperature of the water in the pan during pasteurization, use a thermometer with a scale of up to 150 degrees.

The preservation of canned food prepared by pasteurization is facilitated by the presence of high acidity. You can pasteurize cherries, sour apples, unripe apricots and other acidic fruits for preparations and compotes.

Repeated sterilization. Repeated or multiple (two to three times) sterilization of the same jar of food products containing large quantities of protein (meat, poultry and fish) is carried out at the boiling point of water.

The first sterilization kills mold, yeast and microbes. During the 24-hour period after the first sterilization, the spore forms of microorganisms remaining in the canned food germinate into vegetative forms and are destroyed during secondary sterilization. In some cases, canned food, for example meat and fish, is sterilized a third time a day later.

To re-sterilize at home, you must first seal the jars and put special clips or clips on the lids so that the lids do not come off the jars during sterilization. The clamps or clips are not removed until the cans have completely cooled (after sterilization) to avoid the lids falling off and possible burns.

Salt must be of food quality, clean, without foreign impurities. It is best to take premium or first grade salt. Brine prepared from first grade salt must be filtered to remove insoluble foreign impurities.

Water. To prepare canned food, use only fresh and clean water. It should be soft and not give sediment after boiling. Before drinking, hard water should be boiled, cooled and filtered to remove sediment.

Spices, used for the preparation of canned food, are the following: bitter and allspice peppers in grains and ground, red and green bitter capsicums, bay leaves, cinnamon, cloves and others.

In addition, they use fresh spicy herbs: dill, parsley, horseradish leaves, celery, caraway seeds, etc.

When preparing this or that amount of filling, marinade, syrup, you can use an approximate table of the weight of some products (in g):

Note. The mass (weight) of bulk products is indicated flush with the edge of the spoon, without a slide.

Sterilization.

Sterilization is heating a product to a temperature above 100°C to suppress the vital activity of microorganisms or to completely destroy them.

The main sources of contamination of canned food before sterilization are raw meat, auxiliary materials and spices. Contamination occurs during deboning, trimming, from tools, from the hands of workers, air, containers, etc.

Before sterilization, bacterial contamination is checked in order to clarify the sterilization regimes and storage conditions of the product. The total amount of o/o in 1 g should not exceed:

Stewed meat – 200,000 microbial cells;

Meat pate – 10,000 microbial cells.

Before sterilization, canned food may contain toxigenic spore-forming anaerobes Cl. botulinum and putrefactive anaerobes Cl. sporogenes, Cl. perfringens, Cl. Putrificum, thermophilic microorganisms Bacillus coagulans, etc.

Heating meat at a temperature of 134? C for 5 minutes destroys almost all types of spores. However, exposure to elevated temperatures leads to irreversible, profound chemical changes in the product. In this regard, the most common and maximum permissible temperature for sterilization of meat products is within 120°C. In this case, a heating duration is selected that ensures sufficiently effective neutralization of spore forms of microbes and a sharp decrease in their vital activity (? 40 min).

The sterilization regime is determined by the temperature and duration of its exposure. The correct sterilization regime guarantees a high quality product that meets the requirements of industrial sterility (if 1 g of product contains no more than 11 B. subtilis cells in the absence of botulism and other toxigenic forms).

Concept of sterilization formula.

The jars are loaded into periodic or continuous apparatuses, the installation and jars are heated to the sterilization temperature, sterilization is carried out during the period of death of microorganisms, after the temperature of the apparatus decreases, the jars are unloaded, and the cycle is repeated. The conventional recording of the thermal regime of the apparatus in which canned food is sterilized is called the sterilization formula. For periodic devices, this entry has the form
(A+B+C)/T

where A is the duration of heating of the autoclave from the initial temperature to the sterilization temperature, min; B - duration of sterilization itself, min; C - duration of temperature reduction to a level allowing unloading of the apparatus, min; T-set sterilization temperature, °C.

The temperature in the central zone of the jar lags behind the temperature in the autoclave, which is explained by the low thermal conductivity of the product. The rate of heating of the contents of the jar, in turn, depends on the type of heat transfer: in the liquid component of canned food, heat transfer occurs faster; In the dense part of canned food, heat transfer occurs more slowly.

When determining sterilization modes, you need to know:

1) the temperature of the contents of canned food changes over time during the heating process, and the canned food is heated unevenly by volume;

2) the liquid part of canned food warms up faster than the dense part;

3) the most difficult point to warm up is the one located slightly above the geometric center of the can, since heat transfer from the lid side is inhibited (in non-vacuum canned food) due to the presence of an air bubble in the empty space of the can;

4) the temperature in the central zone of canned food changes over time differently than in the apparatus itself (autoclave).

Thus, the value of the values ​​of A, B, C and T in the sterilization formula characterizes only the operating mode of the device and does not reflect the degree of effectiveness of the heat treatment parameters on the canned product.

Considering the values ​​included in the sterilization formula, one can notice that the T value is chosen as the maximum permissible temperature for a given type of canned food (i.e., causing the smallest changes in the quality indicators of the product), and the values ​​of A and C depend mainly on the design features of the autoclave. The higher the initial temperature of the contents of the jar, the less time A is required to warm it up to the required temperature level.

The value of value A will depend only on the volume and type of container. In this regard, when working on vertical autoclaves, constant set values ​​of A are used: for tin cans with a capacity of up to 1 kg - 20 min, for cans with a larger capacity - 30 min, for glass jars with a capacity of 0.5 kg - 25 min, with a capacity of 1 kg - 30 min.

The value of C is due to the need to equalize the pressure in the sterilized jar with atmospheric pressure before unloading the autoclave. Neglecting the pressure reduction step leads to irreversible deformation of cans or to the breaking of lids from glass containers.

Heating of the product during the sterilization process (stages A and B) is accompanied by an increase in internal pressure inside the jar. The amount of excess internal pressure in the sealed volume of the can depends on the moisture content, the degree of vacuum, the degree of expansion of the product as a result of heating, as well as on the filling factor of the can and the degree of increase in the volume of the container due to thermal expansion of the material and swelling of the ends of the cans.

The degree of thermal expansion of the container material (especially glass) is always lower than the degree of thermal expansion of meat products. Therefore, regulated values ​​for the filling factors of cans are established: for tin cans - 0.85-0.95, for glass cans - less.

The excess pressure in the jar compared to the pressure in the autoclave is mainly due to the pressure of the air present. Evacuation of cans, as well as heating the contents of canned food before capping, can reduce the amount of internal pressure. The level of pressure difference in the jar and in the sterilizing apparatus should not exceed certain limits. With a can diameter of 72.8 mm, the value of Pcr is 138 kN/m2, with a diameter of 153.1 mm, respectively, 39 kN/m2.

To create these conditions, compressed air or water is supplied to the autoclave during sterilization. It is better to create back pressure with water, which has a high thermal conductivity coefficient and at the same time serves as a heating medium.

The reduction in pressure in the apparatus to atmospheric pressure at the end of sterilization, which is necessary to unload the autoclave, leads to an increase in the pressure difference in the jar and the autoclave, since the canned food remains at a high temperature. For this reason, the pressure is equalized gradually by supplying cold water to the autoclave at a pressure equal to that established in it at the end of sterilization. As a result of the rapid cooling of canned food, the internal pressure drops, which allows you to carefully lower the pressure in the autoclave itself. The final cooling temperature for cans before they are unloaded from the autoclave is set to 40-45°C.

The period of time required to reduce the pressure in the apparatus (value C) averages 20-40 minutes.

Sterilization does not always achieve complete death of microorganisms. It depends on the:

1. The more heat-resistant the microorganism, the more difficult it is to cope (spores of Bacillus subtilis can withstand 130? C).

2.Total number of microorganisms.

3. From the consistency and homogeneity of the product (in liquid canned food, the o/o perishes in 25 minutes, and in dense canned food - in 50 minutes).

5. from the presence of fat (E. coli in broth at 100? C dies in 1 second, and in fat - in 30 seconds.

6. from the presence of salt and sugar.

Sterilization in an electromagnetic field by high-frequency (HF) and ultra-high-frequency currents. Sterilization is achieved due to the generation of heat in the cells of microorganisms under the influence of an alternating electromagnetic field. Sterile meat can be obtained by heating to 145°C for 3 minutes. At the same time, HDTV and microwave heating ensure the preservation of the nutritional value of the product.

Sterilization by ionizing radiation. Ionizing radiation includes cathode rays - a flow of fast electrons, X-rays and gamma rays. Ionizing radiation has a high bactericidal effect and is capable of providing complete sterilization without causing heating of the product.

The duration of sterilization by ionizing radiation is several tens of seconds. However, high irradiation intensity leads to changes in the constituent parts of meat. After ionization treatment, the product inside the jar remains raw, so it must be brought to a state of culinary readiness using one of the usual heating methods.

Hot air sterilization. Hot air at a temperature of 120°C circulates in the sterilizer at a speed of 8 - 10 m/s. This method makes it possible to increase heat transfer from the heating medium to canned food and reduce the likelihood of overheating of the surface layers of the product.

Sterilization in batch devices. The most common types of periodic apparatus for sterilizing canned food are autoclaves CP, AB and B6-ISA. Autoclaves are divided into vertical (for sterilizing canned food produced in tin and glass containers, with steam or in water) and horizontal (for sterilizing canned food in tin containers with steam). Temperature and pressure in autoclaves are controlled manually or using pneumatic and electrical software devices - thermostats.

Cans are placed in autoclave baskets manually, by loading them in bulk with a conveyor (with or without a water bath), hydraulic and hydromagnetic stackers. Unloading is carried out by overturning the autoclave baskets.

Rice. 1. Hydrostatic sterilizer A9-FSA:

1 - heating chamber; 2 sterilization chamber; 3 - primary cooling chamber; 4 - additional cooling chamber; 5 - cooling pool; 6 - loading and unloading mechanism; 7 - line for draining water into the sewer; 8 - chain conveyor

Sterilization in continuous devices. Continuous sterilizers are divided into rotary, horizontal conveyor, and hydrostatic. The first two types are rarely used.

Continuous hydrostatic sterilizers use the principle of balancing pressure in the sterilization chamber using hydraulic sluices.

In hydrostatic sterilizers, the length of the conveyor sections in the heating and cooling zones is the same, so the sterilization formula has a symmetrical form A-B-A. The sterilization temperature is maintained by adjusting the position of the water level in the sterilization chamber.

A hydrostatic sterilizer works as follows. Cans are loaded into can carriers of an endless chain conveyor, which delivers them into the shaft of a hydrostatic (water) gateway. After heating, the cans enter the steam sterilizer chamber, are heated to 120 °C and enter the water cooling zone, where the temperature of the canned food drops to 75-80 °C. After leaving the hydrostatic seal, the cans enter an additional water cooling chamber (40-50°C), after which the canned food is unloaded from the sterilizer.

When using continuous sterilizers, there is no need to preheat the device, therefore two values ​​of the sterilization formula A and B form one B' and it takes the form (B" + C)/T.
Pasteurization.

Pasteurization is a type of heat treatment that primarily destroys vegetative forms of microorganisms. In this regard, when producing high-quality pasteurized canned food, a number of additional strict sanitary, hygienic and technological requirements are imposed on raw materials. For such canned food, skin-on pork is usually used; control the pH value of the raw material (for pork the pH should be 5.7-6.2, for beef - 6.3-6.5). During the salting and maturation process, it is recommended to use brine injection, massaging and tumbler. The raw materials are packaged in elliptical or rectangular metal cans with a capacity of 470, 500 and 700 g with simultaneous addition of gelatin (1%). After pressing, the jars are sealed using vacuum sealing machines.

Pasteurization is carried out in vertical or rotary autoclaves. The pasteurization mode includes the time of heating the cans at 100°C (15 min), the period of reducing the temperature in the autoclave to 80°C (15 min), the time of pasteurization itself at 80°C (80-110 min) and cooling to 20°C ( 65-80 min). Depending on the type and weight of canned food, the total duration of the pasteurization process is 165-210 minutes; The heating period for the central part of the product at 80°C is 20-25 minutes.

During pasteurization, the product can retain heat-resistant species of microorganisms that can develop at temperatures up to 60°C, as well as thermophilic species with an optimum development at 53-55°C. To prevent an increase in the contamination of microorganisms, it is necessary to warm up and cool the jars as quickly as possible in order to “pass” the temperature optimum for the development of microorganisms. The most dangerous temperature is considered to be 50 - 68°C.

The amount of jelly in pasteurized products increases (from 8.2 to 23.8%) with increasing heat treatment temperature (from 66 to 94 °C). However, prolonged heating deteriorates the quality of not only the product itself, but also the properties of the jelly (strength, ability to gel). The use of temperatures above 100°C during heat treatment of pasteurized canned food (during the heating period) is accompanied by a deterioration in the juiciness of the product, friability, and a deterioration in consistency.

Tyndalization is a multiple pasteurization process. In this case, canned food is subjected to heat treatment 2-3 times with intervals between heating of 20 - 28 hours. The difference between tindization and conventional sterilization is that each stage of thermal exposure is not enough to achieve the required degree of sterility, however, the total effect of the regime guarantees a certain stability of canned food during storage.

With this method of heat treatment, microbiological stability is ensured by the fact that during the first stage of heating, which is insufficient in terms of the level of sterilizing effect, the majority of vegetative bacterial cells die. Some of them, due to changed environmental conditions, manage to be modified into a spore form. During the intermediate exposure, the spores germinate, and subsequent heating causes the death of the resulting vegetative cells.

Since the degree of impact of pasteurization and tindialization regimes on the components of meat products is less pronounced than during sterilization, pasteurized products have better organoleptic and physicochemical characteristics.

Pasteurized canned food is classified as semi-canned food; their shelf life is at t = 0-5°C and? not higher than 75% 6 months. Tyndized canned food, the shelf life of which at a temperature not exceeding 15°C is 1 year, is classified as “3/4 canned food”. The conditional notation of the pasteurization regime has a form similar to the sterilization formula. It includes several formulas for thermal regimes indicating the periods of holding canned food between heating. Pasteurized canned food is a delicious type of product.

Center for Distance Education "Eidos"

MUNICIPAL EDUCATIONAL INSTITUTION

AGINSKAYA SECONDARY SCHOOL No. 2

Ivannikova Irina, 9th grade student, Aginsk secondary school No. 2

Work on mathematics and biology

Leaders: Tatyana Aleksandrovna Shindyakina, mathematics teacher; Shchedlovskaya Olesya Anatolyevna, biology teacher

RADIATION STERILIZATION OF FOOD PRODUCTS

Why I chose this topic:

I was wondering how radiation sterilization of food occurs

Target:

Find out why radiation technology for food processing has significant advantages over other known methods.

Tasks:

1. Understand the essence of radiation technology for food processing;

2. Find out what are the features of radiation processing of various products;

3. Investigate what biological changes occur in sterilized products;

Idea and problems:

Is it safe to eat products after radiation sterilization? What groups are products subject to sterilization divided into?

INTRODUCTION

There are various food processing methods:

1. Canning at high temperatures is carried out to destroy microflora and inactivate enzymes of food products. These methods include pasteurization and sterilization

2. Ultrasound preservation (more than 20 kHz). This method is used for pasteurization of milk, in the fermentation and non-alcoholic industries, and for sterilization of canned food.

3.Irradiation with ultraviolet rays (UVR). This is irradiation with rays with a wavelength of 60-400 nm. Used for surface treatment of meat carcasses, large fish, sausages, as well as for disinfection of containers, equipment, refrigerators and warehouses.

4.Use of detoxicating filters. The essence of this method is the mechanical separation of goods from spoilage agents using filters with microscopic pores. This method allows you to preserve the nutritional value and organoleptic properties of goods as much as possible and is used for processing milk, beer, juices, wine and other liquid products.

5. Aseptic canning is sterilization of the product at a temperature of 130-150 ° C with subsequent cooling; sterilization of containers by radiation treatment. This treatment is universal and is used for liquid and viscous products (milk, juices, wine, pasta, etc.). In my work, I want to dwell in more detail on the radiation treatment of food products, since radioactive substances can enter the body with food and water through the intestines . How can you protect yourself from radioactive substances, and what food products can be subjected to radiation treatment.

1.Analysis of literature found on the Internet

2.Compare search results

3. Comparison of facts

II WITH SIGNIFICANCE OF THE METHOD OF RADIATION STERILIZATION OF FOOD PRODUCTS

Preservation by ionizing radiation called cold sterilization, or pasteurization, since the sterilizing effect is achieved without increasing the temperature. To process food products, a-, P-radiation, X-rays, and a flow of accelerated electrons are used. Ionizing radiation is based on the ionization of microorganisms, as a result of which they die. Preservation by ionizing radiation includes radiation sterilization (radappertization) of long-term storage products and radurization with pasteurizing doses.

Radiation sterilization of food consists of irradiating food with ionizing radiation under the influence of cobalt or cesium isotopes in order to increase shelf life and destroy pathogens.

It is known that for various reasons: rotting, germination, spoilage by insects, a large number of food products, raw materials, seeds are lost. Thus, the use of radiation sterilization will not only increase the shelf life of certain food products, but also significantly reduce the number of possible food poisoningth

A significant disadvantage of ionizing processing of products is the change in chemical composition and organoleptic properties. In industry, this method is used for processing containers, packaging, and premises.

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