The task of microbiological control is to quickly detect and identify the ways of penetration of microorganisms - pests into production, foci and the degree of their reproduction at individual stages. technological process; preventing the development of foreign microflora through the use of various preventive measures; its active destruction by disinfection in order to obtain high-quality finished products.

Microbiological control should be carried out systematically by factory laboratories. It is carried out at all stages of the technological process, from raw materials to the finished product, on the basis of state standards(GOST), specifications(TU), instructions, rules, guidelines and other regulatory documentation developed for each industry Food Industry. Individual food production facilities have their own microbiological control schemes, which define the objects of control, sampling points, the frequency of control, indicate which microbiological indicator needs to be determined, and provide the norms for permissible total bacterial contamination.

Microbiological control will be effective and will contribute to a significant improvement in the work of the enterprise only if it is combined with sanitary and hygienic control, the purpose of which is the detection of pathogenic microorganisms. They are detected by the content of Escherichia coli. Sanitary and hygienic control includes checking the purity of water, air in industrial premises, food, sanitary condition technological equipment, inventory, containers, hygienic condition service personnel(cleanliness of hands, clothes, etc.). It is carried out both by the microbiological laboratory of the enterprise and by sanitary and epidemiological stations according to the methods approved by the Ministry of Health.

In food production based on the vital activity of microorganisms, systematic microbiological control over the purity of the production culture, the conditions for its storage, breeding, etc. is necessary. Extraneous microorganisms in the production culture are detected by microscopy and inoculation on various nutrient media. Microbiological control of a production culture, in addition to checking its biological purity, also includes determining its physiological state, biochemical activity, the presence of production-valuable properties, reproduction rate, etc. In those food industries where enzyme preparations are used, microbiological control of their activity and biological purity is also mandatory.

Food control. To assess the quality of raw materials, semi-finished products, auxiliary materials, finished products in our country, two indicators are mainly used - MAFAM CoE - the number of mesophilic aerobic and facultative anaerobic microorganisms of colonies forming units and the number of bacteria of the intestinal group (mainly E. coli)

MAFAM is determined mainly by the cup method. Performing an analysis involves four steps:

Preparation of a series of dilutions from selected samples (when examining the surface of a product or equipment, a sample is taken by flushing or scraping from a certain area);

Sowing on a standard dense nutrient medium (to detect bacteria - for meat - peptone agar in Petri dishes);

Growing crops for 24-28 hours in a thermostat at 30°C;

Counting grown colonies. The number of colonies grown on each dish is calculated per 1 g or 1 ml of the product, taking into account the dilution. The final result will be the arithmetic mean of the colony count results in 2 to 3 plates.

The results obtained will be less than the true contamination of the product, since only saprophytic mesophilic bacteria (aerobes and facultative anaerobes) are taken into account by the plate method. Thermophilic and psychrophilic bacteria do not grow due to the temperature discrepancy between the optimal ones; anaerobes do not grow because cultivation is carried out under aerobic conditions; other bacteria (in particular, pathogenic ones) do not grow due to the inconsistency of the nutrient medium and cultivation conditions. Dead cells do not form colonies. However, these microorganisms can be ignored and the analysis error can be neglected, since saprophytes are the main causative agents of food spoilage.

In some industries (canning, sugar, baking, etc.) additional microbiological indicators are used, for example, the number of anaerobic, thermophilic, spore-forming and other microorganisms characteristic of each type of object under study. To account for them, there are special methodological techniques described in the relevant regulatory documentation. For example, to determine the percentage of spore-forming bacteria, inoculation is carried out from test tubes with sample dilutions that have been preheated for several minutes in a boiling water bath. During sowing, only spore-bearing bacteria grow from heated samples, and all the rest from unheated samples. Then the percentage of spore-forming forms of microorganisms is calculated.

The higher the MAFAM index, the more likely it is that pathogenic microorganisms - pathogens of infectious diseases and food poisoning - will enter the object under study. Usually, 1 g (or 1 ml) of a product that has not undergone heat treatment contains no more than 100,000 saprophytic mesophilic bacteria. If their number exceeds 1 million cells, then the stability of the finished product during storage decreases and its use can be harmful to human health.

The definition of coli bacteria is based on the ability of Escherichia coli to ferment lactose to acid and gas. With sanitary and hygienic control of raw materials, semi-finished products, finished products, the study for the presence of bacteria of the intestinal group is limited to the so-called first fermentation test.

The fermentation sample is carried out by seeding in test tubes with a special differential diagnostic medium for Escherichia coli (Kessler medium with lactose) of various volumes (or weights) of the object under study - 1.0; 0.1; 0.01; 0.001 ml (or g). Test tubes with crops are placed in a thermostat at 37 ° C for 24 hours, then they are examined and the fermentation titer is set, i.e. those test tubes in which growth (turbidity of the medium) and gas formation as a result of fermentation are observed. In the absence of gas formation, the control object is considered not contaminated with Escherichia coli. In the presence of gas formation, the number-titer is calculated for various control objects according to special tables. There are norms for the permissible total bacterial contamination and the content of Escherichia coli in control objects.

Water control. For the sanitary and hygienic assessment of water, two microbiological indicators are used: the total number of bacteria in the water and the coli index, which are determined in. in accordance with GOST 18963-73 “Drinking water. Methods of sanitary - bacteriological analysis”.

The total number of bacteria is the number of colonies of aerobic and facultative anaerobic mesophilic saprophytic bacteria that grow when 1 ml of undiluted water is inoculated on meat-peptone agar (MPA) for 24 hours at 37°C.

To assess the quality of water, the most important is not the total number of bacteria, but the presence of pathogenic microorganisms in it. The microbiological indicator of water pollution by pathogenic bacteria of the intestinal group is the coli index. In accordance with GOST 2874-82 “Drinking water. Hygienic requirements and quality control” the total number of bacterial cells in 1 ml of water should not exceed 100, and if the index should not exceed 3 in 1 liter.

Water analysis is carried out when using the city water supply once a quarter, and if available own sources water supply - once a month.

Detection of pathogenic microorganisms in water (causative agents of typhoid fever, cholera and dysentery) is carried out by local sanitary and epidemiological stations only according to epidemiological indicators.

Air control of industrial premises. For the sanitary and hygienic assessment of indoor air, two indicators are determined.

The first is the total number of saprophytic microorganisms in 1 m 3 of air. Air production shops food production is considered clean if it contains no more than 500 saprophytic microorganisms per 1 m 3. The second indicator is the amount in the same volume of air of sanitary - indicative microorganisms - hemolytic streptococci and staphylococci. There are currently no standards for this indicator. Their detection in the air of industrial premises indicates the sanitary problem of this facility and the possibility of infectious diseases among personnel caused by the microflora of the respiratory tract, which is transmitted through the air (tonsillitis, influenza, whooping cough, diphtheria, tuberculosis, etc.). Such air can become a source of food contamination and, therefore, pose a potential hazard to human health. Determination of sanitary-indicative microorganisms in the air is carried out only according to epidemiological indications by sanitary-epidemiological stations.

For sanitary and hygienic air control, sedimentation and aspiration methods of analysis are used, the description of which is available in the regulatory documentation.

Control of equipment, inventory, containers. To prevent contamination by foreign microorganisms of raw materials and semi-finished products during their processing and finished products during storage necessary condition is to maintain cleanliness in the workplace, industrial premises, sanitary treatment of equipment, inventory, containers.

Sanitization means mechanical cleaning of work surfaces from food residues, thorough rinsing with hot water using detergents; disinfection and final thorough rinsing with hot water until the disinfectant (disinfectant) is completely removed. Disinfection aims to destroy the remaining microflora. Disinfection of equipment can be carried out by steaming it with saturated steam, which kills both vegetative cells and spores of microorganisms. Disinfection can also be carried out with chemical disinfectants. The final treatment with hot water plays a dual role: on the one hand, disinfectant residues are removed, on the other hand, the surfaces are heated, which contributes to their rapid drying.

After sanitization, sanitary and hygienic quality control of washing and disinfection of equipment, inventory, containers is carried out, which includes the determination of the total bacterial contamination of washouts from process equipment. Washouts are taken using sterile stainless metal stencils with a cut out middle (cut area 10, 25 or 100 cm 2). This area is wiped with a sterile cotton swab dipped in sterile water in a 10 ml test tube, after which the swab is immersed in this test tube, the contents are thoroughly mixed and 1 ml of the wash is sown on the meat - peptone agar. After thermostating the crops at 30 °C for 24-28 hours, the total bacterial contamination is determined in terms of 1 cm 2 of the surface under study.

In flushes from well-washed equipment, the total number of microorganisms and the coli-index should not exceed their content in clean water entering the sink.

It is impossible to control the quality of washing and disinfection of pipelines, sleeves, hoses in this way, since it is difficult to make flushes from their inner surface using a stencil. In this case, the total number of microorganisms and the coli index are determined in the last wash water by microscopy and inoculation. The total bacterial contamination and the coli index of the wash water should not differ from those of the water used in production.

To control the quality of washing and disinfection of inventory, samples are taken at the moment when the inventory is prepared for work. From small equipment (mixers, probes, thermometers, knives, syringes, etc.), smears are taken with a sterile swab from the entire surface of the object and examined for the total number of microorganisms and for the presence of E. coli. From tables, racks, trays, buckets, shovels, etc., smears are taken with a sterile swab using a burned stencil and similar analyzes are performed.

To control the quality of washing and disinfection of containers (barrels, cans, tanks), samples of the last wash water are microscopically or sown on dense nutrient media. The total number of microorganisms in 1 ml and the coli index should not differ significantly from the contamination of the water used in production.

Checking the cleanliness of hands and clothing of staff. If personal hygiene is not observed (cleanliness of hands, sanitary clothing), especially during manual operations, microorganisms, including pathogenic ones, can get on food products.

Bacterial contamination of hands and clothes is determined by examining the microflora of swabs. In the swabs that are taken before starting work, the total bacterial contamination and the presence of E. coli are usually determined. Hand cleanliness is assessed by the number of microorganisms in 1 ml of flush. The presence of bacteria of the Escherichia coli group in washings from hands and clothes is not allowed. Monitoring compliance with the rules of personal and industrial hygiene carried out by workers of sanitary supervision and sanitary posts.

To comply with the correct sanitary and hygienic regime at food industry enterprises, disinfection is an effective way to destroy and suppress the development of foreign microorganisms.

Disinfection (disinfection) is the destruction of saprophytic microorganisms in environmental objects - pests of this production, which cause damage to raw materials, semi-finished products and finished products, as well as pathogenic microorganisms - pathogens of food infections and food poisoning. Disinfection of equipment, inventory, containers, production and household premises food enterprises is preventive measure to prevent contamination of products by microorganisms. It is carried out systematically in accordance with the established sanitary requirements for each industry. This is the so-called current, or preventive, disinfection.

In addition, it is possible to carry out emergency disinfection at food enterprises according to epidemiological indications: in case of suspected food poisoning, in case of infectious diseases among personnel, when infected raw materials, semi-finished products, containers, etc. are received.

According to the type of active agent, disinfection methods are physical and chemical. Physical means of disinfection include: quartz and ultraviolet irradiation, ultrasound, high temperatures (burning, calcining, boiling, scalding dishes, containers and equipment, treatment with live steam).

Chemical disinfectants include a large number of chemicals with antimicrobial activity. 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. Chemical substances cause either microbicidal (death of microorganisms) or microbostatic action (suspend their growth, but after the removal of this substance, growth resumes again). The nature of the action (microbicidal or microbostatic) depends on the dose of the substance, the time of its exposure, as well as temperature and pH. Small doses of antimicrobial substances often stimulate the development of microorganisms. As temperature rises, the toxicity of many antimicrobial agents tends to increase. Temperature affects not only the activity of the chemical itself, but also microorganisms. At temperatures exceeding the maximum for a given microorganism, even small doses of such substances cause their death. The pH of the medium has a similar effect.

To different antimicrobial substances, the same microorganism exhibits varying degrees sustainability. The same substance can have different effects on different kinds microorganisms - some cause rapid death, others stop their development, others may not have any effect at all. It depends on the presence of spores and capsules that are resistant to chemicals. Antimicrobial substances have a much stronger effect on vegetative cells than on spores.

Of the inorganic substances, salts have a strong antimicrobial effect. heavy metals(mercury, copper, silver), oxidizing agents - (chlorine, ozone, iodine, hydrogen peroxide,. bleaching powder, potassium permanganate), alkalis and acids (caustic soda, sulfurous, hydrofluoric, boric acids), some gases (hydrogen sulfide, carbon monoxide, sulfur dioxide and carbon dioxide). Substances of organic nature (alcohols, phenols, aldehydes, especially formaldehyde) also have a detrimental effect on microorganisms. The mechanism of the destructive action of antimicrobial substances is different and depends on their chemical nature. For example, alcohols, ethers dissolve the lipids of the CPM, as a result of which they easily penetrate the cell and interact with its various components, which disrupts the normal functioning of the cell. Salts of heavy metals, formalin cause rapid coagulation of cytoplasmic proteins, phenols - inactivation of respiratory enzymes, acids and alkalis - hydrolysis of proteins. Chlorine and ozone, which have a strong oxidizing effect, also inactivate enzymes. Antimicrobial chemical substances used as disinfectants and antiseptics.

Disinfectants cause rapid (within a few minutes) death of bacteria, they are more active in environments poor in organic matter, destroy not only vegetative cells, but also spores. They do not cause the emergence of resistant forms of microorganisms. The microbicidal action of antiseptics, unlike disinfectants, manifests itself after 3 hours or more. The greatest activity is manifested in media containing organic matter. Antiseptics destroy only vegetative cells and cause the formation of resistant forms of microorganisms.

Such antimicrobial substances as phenols, chloramine, formalin, in high concentrations (2 - 5%) are disinfectants, but their solutions, diluted 100 - 1000 times, can be used as antiseptics. Many antiseptics are used as food preservatives (sulphurous, benzoic, sorbic acids, juglone, plumbagin, etc.).

Disinfectants in the food industry are used, as a rule, to treat the working surfaces of apparatuses and other technological equipment, inventory, containers, utensils and premises. In the food industry, only such preparations can be used that do not have a toxic effect on the human body, have no smell and taste. In addition, they must have antimicrobial activity at a minimum concentration, be soluble in water, and be effective for short periods of action. Their storage stability is also of great importance. Preparations should not have a destructive effect on the material of the equipment, should be cheap and convenient for transportation.

For the processing of equipment at food industry enterprises, chlorine-containing substances are mainly used, the disinfecting effect of which is due to the release of active chlorine. Usually, solutions containing 150-200 mg of active chlorine per 1 liter are used for disinfection. The most vulnerable places in terms of bacterial contamination are treated with solutions containing 400 mg of active chlorine per 1 liter. The processing time of the equipment must be at least 15 minutes.

Inorganic chlorine-containing disinfectants include: bleach, antiformin (a mixture of bleach, soda ash and caustic soda), sodium hypochlorite; to organic - chloramine B, new synthetic drugs (dichlorodimethylhydantoin) and complex combinations of new chlorine compounds with surfactants (for example, sulfochloranthin, which simultaneously has a wetting, washing and high antimicrobial effect). Formalin (an aqueous solution of formaldehyde), milk of lime, soda ash and caustic soda are also used as disinfectants.

Organic synthetic disinfectants, the so-called quaternary ammonium compounds, have high antimicrobial activity in small doses. Their advantage over existing antimicrobial agents is that they are highly soluble in water, odorless, tasteless, slightly toxic to the human body, do not cause metal corrosion, and do not irritate the skin of personnel hands. Among the domestic drugs in this group, we can name cetozol and catamine-AB. The mechanism of action of this class of compounds on microorganisms is still not entirely clear. It is assumed that they damage the bacterial cell wall, resulting in a sharp increase in cell permeability, protein denaturation, inactivation of enzyme systems and lysis (dissolution) of microorganisms.

Many gaseous substances (formaldehyde, sulfur dioxide, ethylene oxide and β-propiolactone) have a strong bactericidal effect.

When using disinfectants to treat equipment, the following must be observed: general rules: use them only after a thorough mechanical washing of the equipment; disinfectant solutions must be freshly prepared; after disinfection, all treated equipment and communications are thoroughly washed until the disinfectant is completely removed.

Drinking water, as well as industrial water, is usually disinfected in a variety of ways - with the help of strong oxidizing agents (a large amount of water - with chlorine, a small amount - with chlorine compounds, iodine, heavy metal ions), by ozonation, irradiation ultraviolet rays with a wavelength of 200-295 nm, treatment with gamma radiation, ultrasound.

For air disinfection, chlorine-containing preparations and triethylene glycol are most often used in the form of their vapors or aerosols. These disinfectants reduce the total number of microorganisms in the air by more than 90%. Ozonation and ultraviolet irradiation give good results for disinfecting the air of production shops and refrigerators. Periodic application of physical (ventilation, filtration) and chemical methods of disinfection, purification and disinfection of air and their combination with wet cleaning rooms can significantly reduce the bacterial contamination of the air in industrial and amenity premises.

Characteristics of the main groups of sanitary indicative microorganisms (SPM)

SPM is conditionally divided into 3 groups.

The first group includes the inhabitants of the human intestines. They are regarded as indicators of faecal contamination. It includes bacteria of the E. coli group (coliform bacteria), enterococci, sulfite-reducing clostridia (including Clostridium perfringens), coliphages.

The second group includes the inhabitants of the upper respiratory tract and nasopharynx, which are indicators of airborne contamination of the environment. Streptococci and staphylococci have traditionally been included in it, however, at present, only staphylococci are considered SPM of the air environment.

The third group includes saprophytic microorganisms living in external environment. These are indicators of self-cleaning processes. It includes bacteria-ammonifiers and nitrifiers, some spore-forming bacteria, actinomycetes and fungi.

Bacteria of the Escherichia coli group

The advantage of these bacteria as SPM is due to the fact that they are permanent inhabitants of the intestine and are constantly excreted with faeces in environment in large quantities, their number is much higher than other representatives of intestinal microorganisms.

Currently, in accordance with the regulatory and technical documentation, this group includes gram-negative, non-spore-forming rods that ferment lactose and lures that do not have oxidase activity. Coliform bacteria are divided into two subgroups:

a) common coliform bacteria that break down glucose and lactose to acid and gas at 370C for 24 hours;

b) thermotolerant coliform bacteria that break down glucose and lactose to acid and gas at a temperature of 43 ... 44.50C.

10.1. Control of the sanitary condition of enterprises producing semi-finished products, sausages and meat products.

10.1.1. In order to control the sanitary state of production and the effectiveness of sanitization, to prevent the release of low-quality products, microbiological studies of swabs from process equipment, inventory, containers, hands of working personnel are carried out.

Washouts are taken before starting work after preliminary sanitization using sterile moistened swabs made of cotton wool or gauze.

10.1.2. When taking swabs, adhere to the following rules:

Washouts from large equipment and inventory are taken from the surface 100 . A stencil with an area of ​​100 is used to limit surfaces. The stencil is flambéed before each use;

Washouts from small equipment are taken from the entire surface;

When taking swabs from the hands, wipe the palmar surfaces of both hands with a swab, swiping at least 5 times on each palm and fingers, and then wipe the interungual spaces and nails.

10.1.3. In a planned study of equipment, inventory, containers in flushes, the amount of MAFAnM, the presence of BGKP, bacteria of the genus Salmonella, bacteria of the genus Proteus are determined.

In this case, studies are carried out with the following frequency:

Determining the amount of MAFAnM - 2 times a month;

Identification of BGKP - 2 times a month;

Detection of bacteria of the genus Salmonella - 1 time per month;

Detection of bacteria of the genus Proteus - 1 time per month.

Note: The selection of swabs from equipment, inventory, containers is carried out selectively, with the alternation of research objects.

In the study of swabs taken from the hands of workers, the detection of BGKP is carried out. The selection of swabs from the hands is carried out at least once every 15 days.

The schedule for conducting microbiological studies indicating specific objects is approved by the veterinarian of the enterprise or, in his absence (at low-capacity meat processing enterprises), the technologist (or director). Research in the latter case is carried out on a contractual basis by accredited laboratories.

During unscheduled control (to identify a possible source of contamination of the product) additional research for the presence of S.aureus, C.perfingens, etc.

10.1.4. Microbiological studies of washouts are carried out according to the accepted methods set forth in the "Guidelines for sanitary and bacteriological control at enterprises Catering and food trade.

10.1.5. Washes from the surface of technological equipment, small inventory should not contain CGB, bacteria of the genus Salmonella, bacteria of the genus Proteus.

The number of mesophilic aerobic and facultative anaerobic microorganisms should not exceed .

In washings from the hands of workers, the presence of BGKP is not allowed.

10.1.6. Exceeding the allowable amount of MAFAnM and / or the presence of CGB, bacteria of the genus Salmonella, bacteria of the genus Proteus indicate an unsatisfactory state of production.

In this case, unscheduled sanitization (washing and disinfection) is carried out in accordance with the "Instructions for washing and preventive disinfection at enterprises of the meat and poultry processing industry" . At the end of sanitization, a repeated microbiological examination is carried out.

10.2. Water control

10.2.1. Microbiological studies of water are carried out periodically, but at least once a month, as well as at the request of regulatory organizations.

10.2.2. Sampling and microbiological analysis are carried out in accordance with GOST 18963-82.

10.2.3. In the study of water, the number of mesophilic aerobic and facultative anaerobic microorganisms is determined; the number of bacteria of the Escherichia coli group (coli index). In accordance with GOST 2874-82, 1 cm3 should not contain more than; if the index is not more than 3 in 1 liter of water.

The scheme of microbiological examination of water is given in Appendix 6.

10.3. The control of the sanitary condition of the production of canned food is carried out in accordance with the "Instruction on the procedure for the sanitary and technical control of canned food at manufacturing enterprises, wholesale depots, retail and at public catering enterprises", "Instructions on the procedure for microbiological control of the production of pasteurized canned meat", "Sanitary and hygienic requirements for the production of canned meat for feeding young children" .

10.4. The control of the sanitary condition of enterprises producing quick-frozen ready-made meals is carried out in accordance with the "Instructions for microbiological control of the production of quick-frozen ready-made meat dishes" .

10.5. Sanitary control of refrigeration chambers

10.5.1. Microbiological control of the sanitary condition of refrigerating chambers is carried out periodically, but at least once a quarter, as well as after regular or extraordinary disinfection and at the request of regulatory organizations.

10.5.2. Determination of mold infestation of the walls of refrigerating chambers is carried out by scraping. Scrapings are taken from four walls of the chambers in such a way that the sample for analysis is 100. Infection with air molds is carried out by the method of settling spores on a Petri dish for 5 minutes. according to the "Internal sanitary requirements for refrigerators of the meat and dairy industry" .

10.5.3. For chambers with a temperature of minus 12 ° C and below, the amount of mold in the air should not exceed , settled on a cup for 5 minutes: on 1 wall surface - no more. For chambers with a temperature of minus 11.9 ° C and above, the amount of mold in the air should not exceed; on the surface of the walls no more than 1

Instructions for sanitary and microbiological control of brewing and non-alcoholic production
IK 10-04-06-140-87
(approved by the State Agro-Industrial Committee of the USSR on November 4, 1987)

1. General Provisions

Microbiological control at enterprises of the brewing and non-alcoholic industries consists in assessing the sanitary condition of the enterprise based on the determination of sanitary indicative microorganisms and microorganisms - pests of production in raw materials, semi-finished products, finished products and flushing water from equipment.

According to the results of microbiological analyzes, the sanitary and hygienic well-being of the enterprise, compliance with the technological regimes of production, causes and sources of microbial spoilage of the product are judged.

When organizing microbiological control, one should be guided by this instruction, as well as technological instructions for the production of beer, drinks, kvass and sanitary rules for brewing and non-alcoholic industries.

Works on microbiological control are performed by the microbiologist of the enterprise. The results of the analyzes are recorded in the work logs.

Microbiological assessment of the quality of finished products, washing and disinfection of technological equipment should be included in the assessment of the quality of work of shop personnel when paying bonus surcharges.

2. Requirements for the premises for microbiological work

Microbiological work is carried out in a special isolated room - a box with an area of ​​3-5 m 2 . The box consists of a working room and a pre-box, which excludes sharp air circulation and the introduction of microorganisms from the outside. The door to the box is desirable to have a pen-type.

Boxing equipment consists of a table with an easy-to-clean surface, a chair, a spirit lamp (or gas burner) and a bactericidal lamp mounted in a special stand or mounted on the ceiling or wall of the box.

The boxing room is periodically washed and disinfected. Before work, the box is irradiated with a bactericidal lamp for 30-60 minutes. It is forbidden to be in the box when the bactericidal lamp is on. After turning it off, you can work in the box only after 15 - 20 minutes. The bactericidal lamp switch must be located in the dressing room. Immediately before starting work, the microbiologist wipes the surface of the table and handles with alcohol.

Sampling technique for microbiological analysis

With simultaneous sampling for microbiological and chemical analysis, sampling begins with those intended for microbiological analysis.

Samples are taken under conditions that exclude secondary contamination by foreign microorganisms.

Liquids and bulk substances are taken into sterile glassware. Dishes and tools used in sampling are sterilized using one of the methods set out in Appendix 5, paragraph 13. Tools for opening containers, packaging or sampling can be processed ethyl alcohol followed by flaming.

A sample of bulk materials is taken with a metal or porcelain spoon, spatula, sampler from different places and from different depths into one or separate dishes, depending on the purpose of the study. The cork and the neck of the dish are fired in a flame.

A sample of liquid and pasty products from a large container is taken from different depths. If only one sample is taken, mix the contents thoroughly with a pipette or a metal sampler. The sample is transferred into a vessel, the neck of which is burned in a flame.

Fluid samples from containers equipped with a tap are taken as follows:

The tap is washed, wiped with a cotton swab soaked in ethyl alcohol, and burned in the flame of a torch or spirit lamp;

Part of the liquid is drained (from 1 to 10 dm 3, depending on the capacity of the tank and the diameter of the tap);

The sample in the amount required for analysis is taken into a sterile container, the neck of which is preliminarily burned in a flame.

The selected samples are transferred to the laboratory and proceed to the analysis. If it is not possible to start the analysis immediately, the samples are placed in a refrigerator at a temperature of 0 to 5 °C for no more than 6 hours.

The mass (volume) of the sample must be sufficient to fulfill the set of determined microbiological indicators.

The selected sample is intended for preparation, dilution or direct inoculation into nutrient media.

Selected for analysis:

At least 1 pc. - from products in consumer packaging.

Up to 500 cm 3 (g) - liquid, pasty, bulk products.

The number of packaging units to be opened for sampling depends on the size of the lot and is determined in accordance with the current GOST, OST, TU for the relevant products.

Party - a certain set of products of the same type, manufactured on the same day, at the same enterprise, from the same type of raw material, according to the same technology, in the same package, stored and transported under the same conditions and intended for a single transfer or acceptance.

Unit of production - a separate copy of piece products or a quantity of non-piece products determined in accordance with the established procedure.

Sample - a certain number of product units selected for control.

4. Methods for performing microbiological analyzes

Microbiological analyzes of the selected samples are carried out in compliance with the rules of asepsis.

Microbiological analyzes are performed by the following methods:

Seeding the test sample in nutrient media by surface or deep method;

The use of membrane filtration with subsequent transfer of filters to the surface of the nutrient medium;

Microscopy.

A description of these methods is given in Appendix 4 of this manual.

The following abbreviations are used in the text of the instruction:

BGKP - bacteria of the Escherichia coli group;

TMC - total number of microorganisms (total number of mesophilic aerobic and facultative anaerobic microorganisms).

5. Microbiological control of brewing production

In the brewing industry, microbiological control is subject to:

Barley, malt, unmalted materials;

Brewer's yeast;

Beer is ready;

bottles;

capping materials;

Technological equipment, communications, tank trucks (efficiency of sanitization).

Microbiological control is carried out by sampling and determining indicators for production sites according to the scheme (Appendix).

5.1. Barley, malt, unmalted materials.

Beer must be produced from high-quality raw materials that meet the requirements of GOSTs, OSTs and TUs.

In addition to determining the quality of barley, malt and other grain products in accordance with the relevant GOSTs, OSTs and TUs, carried out during the acceptance of raw materials, their external examination is carried out to assess the sanitary condition at the time of receipt. The use of raw materials affected by rot and mold is not allowed. The visual assessment of the quality is carried out by the technologist, head. laboratory, workshop foreman or a person appointed by the order of the director, and writes down the product quality assessment in the journal.

In the production of beer, water is used that meets the requirements of GOST 2874-82 "Drinking Water". A water sample for sanitary and microbiological analysis is taken in production facilities. Water sampling and analyzes are carried out according to GOST 18963-73. Water control is carried out at least once a month.

Bacteriological indicators of water quality must comply with the requirements of GOST 2874-82 "Drinking water".

5.3. Brewer's yeast.

5.3.1. Brewer's yeast from the apparatus of pure cultures or from the last bottle before being transferred to the workshop (with manual breeding) is analyzed by microscopy in a drop of methylene blue with the addition of 10% NaOH or KOH solution. Determine the percentage of non-viable yeast cells (Appendix 4 p. 1.1.2). The presence of bacteria and wild yeast is not allowed.

Wild types of yeast are called, not typical for this production and falling into it by accident.

Take 1 cm3 of yeast from the pure culture apparatus and dilute with sterile water. A series of dilutions is made according to the method described in Appendix 4, paragraph 1.2.1.

By surface method, 0.1 cm 3 suspensions are sown from dilutions (approximately from a dilution of 10 -5) simultaneously on three media: with crystal violet, with lysine and, for control, on wort agar.

The inoculations are incubated for 48 hours at (30 ± 1) ºС. The results are taken into account as follows: both brewer's and all types of wild yeasts grow on wort agar: only wild yeasts of the genus Saccharomyces grow on a medium with crystal violet; on the medium with lysine only wild yeast pp. Candida, Torulopsis, Brettanomyces and others not belonging to the genus Saccharomyces. When incubated for more than 48 hours on selective media, brewer's yeast also begins to grow.

5.3.2. Seed yeast sampling is carried out from each tray or monju. Samples are taken from various levels with a clean glass tube or dilated pipette and placed in small flasks or test tubes.

In seed yeast, microscopy determines fatness by glycogen (Appendix 4, clause 1.1.3), the percentage of non-viable yeast cells and the content of bacteria.

Pay attention to the morphology of yeast cells. The presence of highly elongated or pointed cells indicates degeneration of the culture or wild yeast infection. In this case, inoculation is done on selective media in the same way as for yeast from pure culture apparatuses, but with the addition of streptomycin - 80 mg / dm 3 or chloramphenicol - 50 mg / dm 3 to the nutrient medium, or another antibiotic to suppress bacterial growth.

In seed yeast, the number of bacteria should not exceed 1% of the total number of yeast cells; the number of non-viable yeast cells should be within 5%; 70 - 75% of yeast should contain glycogen.

Yeasts that do not meet these requirements must be subjected to antiseptic treatment, one of the methods of which is given in Appendix 6.

5.4. Wort.

5.4.1. Wort (after the heat exchanger).

In the chilled wort, the total number of microorganisms is determined by seeding 1 cm 3 samples in a deep way on nutrient agar or meat-peptone agar. The sowing technique is described in Appendix 4, paragraph 1.2.2. After incubation at a temperature of (30 ± 1) ºС for 48 hours, the number of grown colonies is counted. The total number of microorganisms in 1 cm3 of wort should not exceed 300.

Sowing 1 cm 3 samples of wort by the deep method on wort agar with chalk reveals acid-forming bacteria. After incubation at (30 ± 1) ºС for 72 h, acid-forming bacteria form zones of chalk dissolution around the grown colonies. Chilled wort should be free of acid-forming bacteria.

5.4.2. The wort from the sterilizer after its cooling when breeding a pure culture of yeast is sown in a volume of 1 cm 3 in a deep way on nutrient agar or meat-peptone agar and wort agar. After incubation for 48 hours, the growth of any form of microorganisms should be absent.

5.5. Finished beer.

Sampling is carried out from each variety in accordance with GOST 12786-80.

Immediately before opening the beer bottles, they are stirred by turning them 10 times from the bottom to the cork or in a circular motion. After opening, the neck of the glass bottles is fired and beer is taken in the amount necessary for analysis. The analysis is carried out from at least two bottles.

Determine the total number of microorganisms on nutrient agar or meat-peptone agar, the presence of bacteria of the Escherichia coli group and the stability of beer in a commercial package at (20 ± 2) ºС).

The total number of microorganisms in 1 cm 3 should not exceed 500 cells.

The method for determining the bacteria of the Escherichia coli group is set out in Appendix 4, paragraph 1.2.4.

For special varieties of bottled beer with a mass fraction of solids in the initial wort of 12% or more, bacteria of the Escherichia coli group are not allowed in 10 cm 3; for mass varieties of bottled beer with a mass fraction of solids in the initial wort of 10-11%, bacteria of the Escherichia coli group are not allowed in 3 cm 3; in draft beer, bacteria of the Escherichia coli group are not allowed in 1 cm 3 .

Pathogenic microorganisms, including salmonella, are not allowed in 25 cm 3 of finished beer. The analysis for pathogenic microorganisms is carried out by the institutions of the sanitary and epidemiological service according to the methods approved by the Ministry of Health of the USSR.

5.6. Correctable marriage of beer.

For analysis, a correctable marriage of beer is taken after heat treatment and cooling to 2 - 5 ° C. The content of microorganisms in 1 cm 3 should not exceed 500 cells.

5.7. Bottles.

5-10 washed bottles are taken from each washing machine. The residual water from all the bottles is poured into one of them and this bottle is closed with a cotton plug. In the laboratory, 1 cm 3 of residual water is inoculated on nutrient agar or meat-peptone agar in a deep way. Crops are incubated at (30 ± 1) ºС for 48 hours. The total number of microorganisms in 1 cm 3 should be no more than 100 in terms of one bottle.

The quality of bottle washing can be determined in another way. Sterile tap water (10% of the volume of the bottle) is poured into one of the bottles and the inner surface of 5-10 bottles is sequentially rinsed with it. Seeding of flush water is carried out in the above way. When calculating the total number of microorganisms in 1 cm 3 of flush water, the volume of rinse water and the number of bottles are taken into account.

5.8. Closing material.

Crown caps are taken from the workplace with sterile tweezers in the amount of 10 pieces into a sterile wide-mouth flask, filled with 100 cm 3 of sterile water and shaken for 5 minutes. Determination of the total number of microorganisms is carried out by inoculation of 1 cm 3 washings in a deep way on meat-peptone agar or on nutrient agar. The number of microorganisms in terms of one sample should not exceed 100.

5.9. Air.

To determine the number of microorganisms in the air of the department of pure cultures, the sedimentation method (settlement method) is used. Petri dishes with meat-peptone or nutrient agar and wort agar are transferred to the room where the air is examined. The lids are shifted so that the entire surface of the agar plate is completely exposed. The cups are left open for 5, 10 or 15 minutes, after which the lid is closed and the cups are placed in a thermostat at (30 ± 1) ºС for 24 - 48 hours.

The number of microorganisms in 1 m 3 of air is determined according to the formula proposed by Omelyansky:

where a- number of grown colonies (average value);

S- area of ​​the Petri dish, cm 2 ;

T- exposure time, min;

100 - recalculation of the cup area per 100 cm 2;

100 - recalculation for 1 m 3 of air;

5 - exposure of the cup according to Omelyansky (in 5 minutes, as many microorganisms settle on a Petri dish with an area of ​​100 cm 2 as they are contained in 10 liters of air).

The air is considered clean if it contains no more than 500 microorganisms per 1 m 3, in addition, there should be no extraneous yeast in the air of the pure cultures department.

The same culture media are used to control the air used to aerate the pure culture. Petri dishes with solidified nutrient medium in open form substitute for 1 min under a stream of air, cover with a lid and incubate at (30 ± 1) ºС. The air blown into the apparatus of pure cultures must not contain extraneous yeast cells, lactic acid bacteria, mold spores.

Similarly, they check the air used for technological needs in the filtration department, the bottling shop. There should not be more than 50 cells of microorganisms on one Petri dish.

6. Microbiological control of the production of soft drinks and kvass

In the production of soft drinks, the following objects are subject to microbiological control:

Drinking water, granulated sugar, liquid sugar, fruit juices, concentrates of drinks and kvass wort;

Sugar syrup, blended syrups;

Ready-made drinks, bread kvass, commercial syrups;

Bottles, closures;

Technological equipment, communications, tank trucks.

Microbiological control of the production of soft drinks is carried out by sampling and determining indicators for production sites according to the scheme (Appendix).

When determining the content of microorganisms in raw materials, semi-finished products and the finished product, two methods of sowing are used:

The method of sowing the test material directly into the nutrient medium: superficially (0.1 cm 3) or deep (1.0 cm 3);

The method of membrane filters, which allows concentrating microorganisms on the membrane from a large volume of the material under study, with the subsequent transfer of the filter to the surface of the nutrient medium, for growing microorganisms.

The membrane filter method is used when analyzing samples with low contamination (drinking water, beverage concentrates, finished drinks with a preservative, etc.).

When determining the content of microorganisms in samples with increased contamination (alcoholized juices, blended syrups, drinks without preservatives); and also in cases of absence of membranes it is necessary to use the method of direct inoculation on a nutrient medium.

When recording test results, the seeding method must be specified. The description of the methods is given in the appendix.

6.1. Drinking water. Quality drinking water, used at the enterprises of the non-alcoholic industry, must comply with the requirements of GOST 2874-82 "Drinking water". Water is tested according to the following indicators:

The number of bacteria of the Escherichia coli group (coli index).

In 1 cm 3 of water, no more than 100 cells of microorganisms are allowed, and if the index should not exceed 3 in 1 dm 3 of water.

6.2. Sugar sand. In refined granulated sugar, the total number of microorganisms is determined. For this, granulated sugar in an amount of 1 g is dissolved in 5 cm 3 of sterile drinking water. For inoculation, take 1.0 cm 3 of the prepared solution and inoculate in a deep way on nutrient agar or meat-peptone agar, incubate (30 ± 1) ºС for 48 hours.

When calculating the number of microorganisms, dilution, the sown volume are taken into account and recalculated for 1 g of granulated sugar. Not more than 1000 cells of microorganisms in 1 g of sand are allowed.

6.3. Liquid sugar is checked for the following indicators:

The total number of microorganisms - seeding 1.0 cm 3 deep method on nutrient agar or meat-peptone agar;

Yeast - sowing 1.0 cm 3 in a deep way on wort agar;

Leikonostok - sowing 1 cm 3 (without dilution) in a 100 cm 3 flask with 5 cm 3 yeast water in 10% sucrose.

The following numbers of microorganism cells are allowed in liquid sugar, in 1 cm 3:

The total number of microorganisms - no more than 20;

Yeast - absent.

Leuconostok in 1 cm 3 of liquid sugar is absent.

Leuconostok is recognized by the mucus of yeast water with sucrose.

6.4. Sugar syrup. Indicators of microbiological contamination of the syrup and the course of analysis are similar to liquid sugar.

The following numbers of microorganism cells are allowed in 1 cm 3 of sugar syrup:

the number of microorganisms - no more than 20,

yeast - absent,

leuconostok in 1 cm 3 of syrup is absent.

6.5. Natural fruit and berry juices (alcoholized and concentrated).

Alcoholic juices are often heavily contaminated with yeast, so their determination is carried out by seeding 0.1 cm 3 in a superficial way on wort agar.

Not more than 300 yeast cells are allowed in 1 cm 3 of alcoholized juice.

Juices with a higher contamination should be used for the preparation of blended syrups in a hot way.

In juices concentrated in accordance with GOST 18192-72, an analysis for a spoilage agent (yeast) is carried out, if necessary, to confirm microbial spoilage in accordance with GOST 10444.0-75 (fermentation, bombardment). In this case, the juice, in the amount of 0.1 cm 3 , is sown by a surface method on wort agar.

6.6. Concentrate of fruit and berry drinks. The content of yeast in beverage concentrates is determined by seeding on wort agar 3 cm 3 by the method of membrane filters. Concentrates for analysis are collected with a pipette with an extended end (slightly broken off).

The drink concentrate in the amount of 3 cm 3 is diluted with sterile drinking water 5 times and filtered. In case of difficult filtration caused by poor clarification of the juice, the sample is filtered through a pre-filter. No. 10 MFA-MA for removal of large particles. To do this, filter No. 10 is placed in a filter device above filter No. 6. After filtration, both filters are transferred to wort agar. When calculating the results of the analysis, the growth of yeast on both filters, as well as the volume of the sample taken and its dilution are taken into account.

In beverage concentrates (dry matter content 70%), yeast in 3 cm 3 is absent.

6.7. Kvass wort concentrate. The yeast content is determined by seeding 0.1 cm 3 surface method on wort agar. Allowed in 1 cm 3 the content of yeast is not more than 50 cells.

6.8. Blended syrups are checked for the presence of yeast.

Syrups without preservatives are sown in the amount of 0.1 cm 3 by surface method on wort agar. Not more than 300 cells per 1 cm 3 are allowed in syrup without preservative.

Syrups with preservatives are checked by the membrane filter method in the following quantities:

Syrups on infusions and flavorings - 1.0 cm 3;

Syrups on fruit juices - 0.5 cm 3.

After filtering the syrup with a preservative, the filter is washed with 2–3 cm 3 of sterile drinking water and transferred to a Petri dish with wort agar.

In the absence of membranes, seeding is carried out by a surface method in the amount of 0.1 cm 3 per wort agar.

The presence of yeast in blended syrups with a preservative in 1 cm 3 is allowed:

On infusions and flavorings - single cells (no more than 5);

On fruit and berry juices - no more than 30.

6.9. Ready-made drinks are checked for the content of yeast and bacteria of the Escherichia coli group (coli index).

To determine yeast, drinks without a preservative are sown in an amount of 0.1 cm 3 by a surface method on wort agar.

The presence of yeast in 1 cm 3 of a drink without preservative is allowed - no more than 100 cells.

Drinks with preservatives are checked by the method of membrane filters or surface seeding. The course of analysis is similar to blended syrups.

The following quantities of yeast are allowed in drinks with a preservative, in 1 cm 3:

On infusions and flavorings - single yeast cells, no more than 10;

On fruit juices - no more than 50 cells.

Drinks based on grain raw materials, pasteurized in bottles, are checked for yeast content by the method of membrane filters (seeded volume - 40 cm 3).

There are no yeasts in the sown volume.

The determination of bacteria of the Escherichia coli group is carried out by the generally accepted method in accordance with GOST 18963-73 and clause 1.2.4 of Appendix 4. The coli index of carbonated drinks should be no more than 3.

6.10. Commercial syrups. Syrups are tested for resistance in accordance with OST 18-130-82 at (20 ± 2) ºС.

6.11. Bottles, closures. For the definition and course of the analysis, see p.; .

6.12. Bread kvass obtained by fermentation.

In the production of bread kvass, the following indicators are determined:

The total number of bacteria of the Escherichia coli group in drinking water used to dilute the concentrate (coli index), in accordance with GOST 18963-73;

The presence of leukonostok in ready-made kvass wort with sugar syrup, see the method for determining liquid sugar p. (absent in 1 cm 3);

Bacteria of the group of Escherichia coli (BGKP) in ready-made kvass.

The method for determining BGKP in kvass is set out in Appendix 4, paragraphs 1.2, 4.2.

In bread kvass on pure cultures, BGKP is not allowed in 10 cm 3.

In bread kvass on baker's yeast BGKP is not allowed in 1.0 cm 3 .

Pathogenic microorganisms, including salmonella, are not allowed in 25 cm 3 of ready-made drinks and kvass. The analysis for pathogenic microorganisms is carried out by the institutions of the sanitary and epidemiological service according to the methods approved by the Ministry of Health of the USSR.

7. The quality of sanitization of technological equipment and communications in the production of beer, soft drinks and kvass

Sanitary and microbiological control is carried out after washing and disinfection, carried out in accordance with the "Sanitary Rules for Brewing and Non-Alcoholic Industry Enterprises", by sowing the selected samples of the last flush water.

Sampling is carried out after the complete removal of detergents and disinfectants.

7.1. In the production of beer, the quality of sanitization of the following equipment and communications is checked:

Key vats;

Malting boxes;

Unit for the production of malt in a static way;

Hopper for malt (wet and dry crushing);

Installation for water treatment;

Settling tanks, plates, hydrocyclone tanks;

Collections for protein sludge;

Wort separators;

Open irrigation coolers;

Plate heat exchangers;

Tubular heat exchangers;

Hoses, pipelines, wort pipelines in all workshops and departments;

Wash water collection;

Pre-fermentation vats (open and closed);

Main fermentation vats (open and closed);

Tanks for fermentation;

Cylindrical-conical tanks;

Tanks of semi-continuous fermentation lines;

Vessels for the separation of pure yeast culture;

Equipment for storage of deposited yeast;

Piping system;

Lightening filters;

Filters providing;

Finished beer separators;

Faucets;

Carbonizers;

Capacities for correctable marriage of beer;

Collections of finished beer;

washed bottles;

filling machine;

Tank trucks (beer trucks);

Merniki for brewers.

In the selected samples determine:

The total number of cells of microorganisms;

When determining the total number of microorganisms, 1 cm 3 of wash water is sown in the deep method on nutrient agar or meat-peptone agar, incubated at (30 ± 1) ° C for 48 hours. With good quality washing and disinfection, the number of microorganisms in the last wash water should be close to the number of microorganisms in the water entering the sink, i.e. no more than 100 in 1 cm 3.

Bacteria of the Escherichia coli group are determined according to the method described in Appendix 4, clause 1.2.4.4. BGKP should be absent in 100 cm 3 of flush water.

7.2. In the production of soft drinks, the quality of sanitization of the following equipment and communications is checked:

Containers for storing juice, liquid sugar;

Tanks for storing kvass wort concentrate;

Containers for sugar syrup;

Blending and pressure tanks;

Filter presses, separators;

Synchronous mixing plants;

filling machines;

washed bottles;

capping material;

Tanks for preparation of distribution of microorganisms in the production of bread kvass;

Concentrate dilution container;

Fermentation and blending containers;

Cylindrical-conical fermentation tanks ShCh-VTSN-50;

Dispensers, hoses, piping systems;

Tanks for finished kvass, collectors;

Tank trucks for kvass.

7.2.1. In the samples taken during the production of carbonated drinks, the following is determined:

The total number of microorganisms;

Coli-index;

For the determination of the total number of microorganisms in wash water, see p.

With a good quality of washing and disinfection, the number of microorganisms in the last flush water should be close to the number of microorganisms in the water entering the washing of equipment, i.e. no more than 100 in 1 cm 3.

Bacteria of the Escherichia coli group are determined by methods in accordance with GOST 18963-73 “Drinking water. Methods of sanitary-bacteriological analysis. Coli-index 3.

Yeast in wash water is determined by seeding 1 cm 3 in a deep way on wort agar. Incubate at (30 ± 1) ° C for 48 hours. Breaks or swelling of the agar plate indicate the presence of yeast in the wash water and are not subject to quantitative calculation.

With a thorough washing and disinfection, yeast in 1 cm 3 of flushing water should be absent.

7.2.2. In the selected samples of wash water from the production of bread kvass, the following is determined:

The total number of microorganisms;

Bacteria of the Escherichia coli group.

The total number of microorganisms should be close to the number of microorganisms in the water entering the sink, i.e. no more than 100 in 1 cm 3. BGKP should be absent in 100 cm 3 of flush water (see Appendix 4, paragraph 1.2.4.4).

7.3. For a quick assessment of the quality of washing and disinfection of tankers for beer and kvass, 10 cm 3 of the last wash water is centrifuged at 1500 - 2000 rpm for 10 minutes. The centrifugate is drained, the precipitate is microscopically. In 10 fields of view there should be no more than 5 - 6 cells, the presence of microorganisms in each field of view indicates an unsatisfactory washing.

7.4. In case of non-compliance with the requirements for sanitization of equipment and communications, the microbiologist is obliged to report to the head production laboratory, which brings the results of the control to the attention of the shop manager and requires additional washing and disinfection of process equipment.

The disadvantages of the disinfection carried out are taken into account during subsequent processing, while it is necessary to pay attention to the thoroughness of mechanical washing, the concentration of the disinfectant, the exposure time, and the operating modes of the bottle washing machine.

8. Sanitary standards

"Microbiological standards for soft drinks and beer"