Microbiological analysis
Microbiological analyzes are performed in many different fields. Some of these are purely chemical analyzes and some of them are difficult and dangerous analyzes that can only be done by experienced and expert microbiologists. As such, there are many different methods of analysis of microbiology originating from different disciplines and different materials.
As new approaches to food safety have emerged in recent years, improvements and changes in analysis methods have been taking place. In this parallel, accreditation, calibration, automation, validation (validation of the applied methods), verification (determination of the correctness of the standard methods applied) and measurement uncertainty have started to gain weight in the laboratories. Genetic and serological-based analyzes have also become increasingly common (serological, blood tests that determine the presence of antibodies produced against certain microorganisms).
Microbiological analysis has become increasingly important as the number of institutions that attach importance to quality in food sector in our country. Today, the world and in our country still apply the classical methods and the American Food and Drug Administration (FDA) and International Standards Organization (ISO) are based on these methods. However, studies in this area are gaining momentum and especially genetic and serological based analyzes will be valid as standard analysis methods in a short period of time.
Today, microbiological analyzes of foods can be grouped under the following headings: counts, var-no tests, biological stability tests, toxin tests and other tests.
When food microbiology is mentioned, the first step is the control of unwanted microorganisms in foods. The purpose of the control here is not only laboratory analysis. The main objective is to prevent the transmission and development of microorganisms in foods. In terms of standards, the prevention of contamination is provided by EUREPGAP standards (good agricultural practices) in terms of raw materials, and the prevention of development is provided by HACCP standards (hazard analysis and critical control points).
Undesirable microorganisms in food, such as a mold used for making moldy cheese, are considered to be undesirable microorganisms if they are transmitted to kashar cheese. Although this does not cause any health problems, it is an indication that the manufacturer does not comply with the basic hygiene conditions. This is understandable only when total mold and yeast counts are made in kashar cheese.
Numerous microbiological analyzes of food products are performed by authorized laboratories in the food sector. The main tests, measurements and analyzes are as follows:
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Microbiological analyzes |
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Number of aerobic bacteria (number of aerobic mesophilic bacteria, number of aerobic colonies) |
Mold and yeast count (rapid test) |
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Aerobic bacteria count (aerobic mesophilic bacteria count, aerobic colony count) (rapid test) |
Lactic acid bacteria count (rapid test) |
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Determination of Alicyclobacillus acidoterrestris |
Determination of the number of lipolytic bacteria |
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Alicyclobacillus spp. determination |
Determination of Listeria monocytogenes |
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Determination of anaerobic bacteria count |
Searching Listeria monocytogenes (rapid test) |
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Determination of acid-forming bacteria |
Listeria spp. analysis |
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Determination of Bacillus cereus |
Listeria spp. Analysis (fast test) (food and feed) |
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Bacillus spp. isolation and identification analysis |
Determination of mushroom count |
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Bacterial culture |
Determination of osmophilic yeast |
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Bombage and leakage control (excluding incubation) |
Determination of proteolytic bacteria count |
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Determination of Clostridium botulinum toxin |
Pseudomonas spp. determination |
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Determination of Clostrodium perfringens |
Determination of Pseudomonas aeruginosa |
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Direct microscopic counting |
Resazurine test |
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Determination of flat-sour (number of bacteria souring flat) |
Determination of Rope Sport |
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E. coli (EMS) ISO method |
Salmonella search (rapid test) |
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E. coli determination (solid medium) |
Salmonella spp. determination |
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E. coli O104: Determination of H4 |
Salmonella enterica serotyping analysis |
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E. coli O157: Determination of H7 |
Searching for Shigella |
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E. coli O157: H7 searching quick test |
Somatic cell count (microscopic) |
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E. coli count (rapid test) |
Somatic cell count (with device) |
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Determination of Enterobacter sakazakii (cronobacter spp.) |
Staphylococcal enterotoxin (A, B, C, D, E) analysis (in all foods) (real time-PCR) |
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Enterobacter sakazakii (rapid test) (cronobacter spp.) |
Staphylococcal enterotoxin analysis (single analysis) |
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Enterobacteriaceae count |
Determination of Staphylococcus aureus (coagulase positive staphylococ) |
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Enterobacteriaceae count (rapid test) |
Staphylococcus aureus count (rapid test) (coagulase positive staphylococ) |
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Fecal streptococcus (enterococcus) count |
Sterility control (UHT milk, canned food for infants and young children) |
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Incubation (stability) (10 days) |
Sterilization control (biochemical) |
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Incubation (stability) (15 days) |
Determination of sulphide reducing anaerobic |
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Incubation (stability) (7 days) |
Searching for thermotolerant campylobacter (rapid test) |
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Coliform (EMS) ISO method |
Search for thermotolerant campylobacter (classical method) |
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Coliform determination (solid media) |
Determination of commercial sterility (canned and canned products) |
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Coliform bacteria count (rapid test) |
Determination of total number of specific microorganisms (in yogurt) |
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Coliform, fecal coliform, e. Determination of coli (EMS) (FDA BAM) |
Determination of Vibrio cholerae |
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Mold count (with Howard slide) |
Determination of Vibrio parahaemolyticus |
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Mold diagnosis |
Vibrio parahaemolyticus (rapid test) |
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Mold and yeast count |
Vibrio spp. Searching |
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Lactic acid bacteria count |
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