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To assess the quality of raw materials, semi-finished products, auxiliary materials, finished products in our country, two indicators are mainly used — total bacterial contamination (OBO) and the number of bacteria of the intestinal group (mainly Escherichia coli).
General bacterial contamination. It is determined mainly by the cup method. The analysis includes four stages: preparing a series of dilutions from the selected samples (when examining the surface of a product or equipment, a sample is taken by flushing or scraping from a certain area); plating on a standard solid nutrient medium (for detection of bacteria - on meat and 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 plate is counted on 1 g or 1 ml of the product, taking into account the dilution. The final result will be the arithmetic average of the results of counting colonies in 2-3 cups.
The results obtained will be less than the true seeding of the product, since only the saprophytic mesophilic bacteria (aerobes and facultative anaerobes) are taken into account by the cup method. Thermophilic and psychrophilic bacteria do not grow due to mismatch in temperature; anaerobes do not grow, because the cultivation is carried out under aerobic conditions; other bacteria (in particular, pathogenic) do not grow due to the mismatch of the culture medium and cultivation conditions. Dead cells do not form colonies. However, these microorganisms can be ignored and neglected as an analysis error, 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. For their accounting, there are special teaching methods described in the relevant regulatory documentation.
For example, to determine the percentage of spore-forming bacteria, inoculation is carried out from test tubes with dilutions of samples 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 ones. Then calculate the percentage of spore-forming forms of microorganisms.
The higher the indicator of total bacterial contamination, the greater the likelihood of pathogenic microorganisms — pathogens of infectious diseases and food poisoning — getting into the studied object. Typically, 1 g (or 1 ml) of a product that has not undergone heat treatment contains no more than 100 thousand saprophytic mesophilic bacteria. If their number exceeds 1 million cells, then the shelf life of the finished product decreases and its use can harm human health.
The definition of gut bacteria is based on the ability of E. coli to ferment lactose to acid and gas. When sanitary-hygienic control of raw materials, semi-finished products, finished products, the study of the presence of bacteria of the intestinal group is limited by the so-called first fermentation test.
A fermentation test is carried out by inoculation into test tubes with a special differential diagnostic medium for Escherichia coli (Kessler medium with lactose) of various volumes (or weights) of the test object — 1.0; 0.1; 0.01; 0.001 ml (or g). Inoculated tubes are placed in a thermostat at 37 ° C for 24 hours, then they are examined and a fermentation titer is installed, i.e. those 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 E. coli. In the presence of gas generation, the coli titer for various control objects is calculated according to special tables. There are norms of permissible total bacterial contamination and the content of E. coli in control objects.
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- SANITARY CONTROL OF VEGETABLE FOOD PRODUCTS
SANITARY CONTROL OF VEGETABLE FOOD
- Sanitary control over the production and use of materials intended for contact with food
At the food industry enterprises of the corresponding branches of agriculture, public catering and trade systems, various products (utensils, containers, packaging, equipment, implements, consumer goods, etc.) are used in everyday life, made of various materials: metals and alloys, porcelain, faience, glass and a relatively new type of materials (see, below) - polymer.
- Hygienic principles of regulation of ChVV in a daily diet, food products
In food hygiene, the basic regulation is the allowable daily dose (DSD) of normalized FVC. ChDV DSD is the maximum dose (in milligrams per 1 kg of body weight), the daily oral intake of which is harmless throughout a person’s life, i.e. It does not adversely affect the life and health of present and future generations. Multiplying DSD by human body weight (60
- Test. Physiological and hygienic value of food products. Energy Evaluation of Diet, 2009
Introduction.Physiological role and hygienic value of proteins. Physiological role and hygienic value of fats. Physiological role and hygienic value of carbohydrates. Physiological and hygienic assessment of the main trace elements. Vitamins. Energy assessment of food ration.
- Sanitary control of the use of food additives
Food additives (preservatives, colorants, flavorings and flavorings, antioxidants, stabilizers, enzyme preparations, salt and sugar substitutes, etc.) are introduced into food products at various stages of production, storage and transportation to give them certain (necessary from a technological point of view) properties : preservation of natural qualities, nutritional properties and
- FOOD CERTIFICATION
Quality management of food products is the main means of achieving and maintaining the competitiveness of the enterprise. Product quality is created at all stages of production. A food product cannot be of high quality if it is not needed by the consumer, although it meets all the requirements and specifications. The basis of product quality is the determination of consumer needs, i.e.
- GENERAL PRINCIPLES OF MICROBIOLOGICAL AND SANITARY-HYGIENIC CONTROL IN THE FOOD INDUSTRY
The task of microbiological control is to quickly detect and identify the pathways of penetration of pest microorganisms into production, foci and their degree of reproduction at certain stages of the technological process; preventing the development of extraneous microflora through the use of various preventive measures; active destruction by disinfection in order to obtain
- Sanitary requirements for food transportation
For transportation of food special transport is used. Sanitary control over the transportation of food products is carried out periodically at transport bases, as well as during the delivery of products to their destination, during their unloading at public catering establishments and other facilities. Vehicles must be specialized for the transport of a particular type of food
- VETERINARY AND SANITARY QUALITY CONTROL OF ANIMAL PRODUCTS IN THE MARKETS
The quality of food products of animal origin during their implementation on collective farm breakthroughs is controlled by veterinary specialists of the laboratories of veterinary and sanitary expertise. Laboratories of veterinary and sanitary expertise organize in the market in the prescribed manner. They are part of the city or district station for combating animal diseases, the district (inter-district) veterinary laboratory.
- Food Sanitary Examination
Sanitary examination of food products (sanitary-hygienic assessment) is aimed at identifying properties that characterize the nutritional value or harmlessness of products for human health. Its task is to check the qualitative and quantitative indicators provided by GOST (OST) for a given type of food product, and especially to determine the suitability for eating non-standard
- FOOD CONSERVATION
Due to the fact that only benign food products are subject to canning, it is necessary to dwell on the influence of microorganisms and environmental factors on quality
- FOOD SAFETY
To prevent diarrhea and diseases transmitted by water and food, which are one of the main causes of poor nutrition, stopping physical development and relapsing diseases, safe food, clean water and proper hygiene are vital. Breastfeeding should be encouraged even when an alarming possibility
- FOOD VALUE OF VEGETABLE PRODUCTS
The nutritional value of plant products depends on their chemical composition. Plant foods (vegetables, root crops, fruits, berries, beans and some cereals, mushrooms) occupy a large place in human nutrition. They are the main source of carbohydrates, vitamins and minerals. Many plant foods are widely used as seasonings (spices, spices) to
- Sanitary control of the use of pesticides and their residues in food
In carrying out current sanitary supervision on the protection of food products from pollution by pesticides, one should be guided by the “Sanitary rules for the storage, transportation and use of pesticides (pesticides) in agriculture” (No. 1123-73), other instructive, regulatory and guidance materials (see Order of the Ministry of Health of the USSR, No. 874 of