Microbiological Analysis in Foods: Safe Food

Microbiological Studies in Foods and Food Safety

Microbiological Analysis in Foods

Microbiological Analysis; Microorganisms that can be encountered in every aspect of our lives; It is expressed as all of the studies carried out to detect the presence, quantity, types and toxins that pose a serious risk to human health.

The effectiveness of microbiological tests is of vital importance as the damage caused by microorganisms taken directly or indirectly into the body with food can cause serious health problems as well as deaths.

In food microbiology, not only harmful microorganisms are analyzed, but also beneficial microorganisms. Beneficial microorganisms such as probiotics and starter cultures are important for improving quality in food production, managing fermentation processes and supporting human health. Especially in the analysis of beneficial microorganisms found in fermented foods such as yogurt, cheese, kefir, the aim is to detect the number of microorganisms above the defined limit, unlike the analysis of pathogenic microorganisms.

Classification of Analyses

Microbiological analyses in food are classified as qualitative, quantitative and most probable number (EMS) analyses according to the way the analysis methods are measured and the way the results are evaluated. This classification is based on whether the data obtained as a result of the analysis is qualitative or quantitative and whether the method of counting microorganisms is based on direct or statistical estimation.

Qualitative Microbiological Analysis determines the presence or absence of a specific microorganism. It is widely used especially in sensitive foods (ready meals, dairy products, meat products) to determine the presence of pathological microorganisms (Salmonella spp., Listeria monocytogenes, Escherichia coli O157). This technique is used to search for dangerous pathogenic microorganisms and the analysis process usually ends with the identification of the detected microorganism.
Quantitative Microbiological Analysis determines the numerical density of a particular microorganism. It is used to determine Aerobic Mesophilic Bacteria Count, Yeast and Mold Count, etc., especially for assessing production hygiene and food safety criteria.
In Most Probable Number (EMS) Analysis, the number of microorganisms is determined by statistical estimation. it is often used to estimate microorganisms at low densities, especially for milk and liquid samples.

Microbiological Hazards

Microbiological analyses are vital for ensuring food safety, protecting consumers and preventing outbreaks that threaten public health.

According to the World Health Organization (WHO), an estimated 600 million people (almost 1 in 10 people worldwide) get sick after eating contaminated food and 420,000 people die each year. Children under the age of 5 carry 40% of the burden of foodborne illness, resulting in 125,000 deaths each year.

Microorganisms that pose a microbiological hazard in food are divided into different categories.

Dangerous Pathogens: Microorganisms that can cause foodborne diseases or outbreaks and pose serious health risks even at low doses. Examples include Listeria monocytogenes, Escherichia coli O157, Salmonella spp. Analyses are performed on a 25 g food sample and no pathogenic microorganisms should be detected in 25 g.
Pathogens: Microorganisms that can cause infection in individuals with weak immune systems and in some cases cause food poisoning by producing toxins. Examples include Staphylococcus aureus, Bacillus cereus, Clostridium perfringens. Analyses are performed on 10 g of food sample and the amounts allowed to be present in the gram of food sample are defined in the regulation.
Hygiene Indicator Microorganisms: These are microorganisms used to evaluate the hygiene conditions in the production stages of foods. They provide information about the level of cleanliness in the production environment. Examples include Enterobacteriaceae, Coliform Bacteria, Escherichia coli. Analyses are performed on 10 g of food sample and the amounts allowed to be present in the gram of food sample are defined in the regulation.
Beneficial Microorganisms: Microorganisms that manage the desired biological processes in foods and have positive effects on health with their fermentation and probiotic properties. An example is the Specific Microorganism Count analysis where Lactobacillus bulgaricus and Streptococcus thermophilus species are sought.

Below are some of the analyzes we provide according to analysis categories.

Quantitative Analysis	Qualitative Analyses	Analyzes with EMS Method
Aerobic Colony Count*	Salmonella spp. Search*	E. coli Count
E. coli Count*	Listeria spp. Search*	Coagulase Positive Staphylococci (S. aureus and other Species) Count
Coliform Bacteria Count*	Listeria monocytogenes Search*	Rope Sports
Enterobacteriaceae Count*	E. coli O157 Search*
Yeast and Mold Count*	Campylobacter spp. Search
Coagulase Positive taphylococcus (S. aureus and other Species) Count*	Vibrio spp. Search
B. cereus Count*	E. coli Search
Clostridium perfringens and Spore Count	Cronobacter spp. Search
Enumeration of sulfite-reducing clostridium spp. and spores	Staphylococcus enterotoxin
Mesophilic Aerobic Bacteria Count
Pseudomonas spp. Count
Anaerobic Bacteria Count
Lactic Acid Bacteria Count
Enterococcus Count
Characteristic Microorganism Count

Analyzes marked with (*) are also run by the rapid method as an alternative to the classical method.

What are Microbiological Criteria?

The Turkish Food Codex Regulation on Microbiological Criteria, prepared in parallel with the European Union Commission Regulation No. 2073/2005/EC on Microbiological Criteria for Foodstuffs, defines the microbiological criteria of foods, the rules that food operators must comply with and apply, and certain limit values for pathogenic microorganisms and their toxins and microorganisms that cause spoilage.

The Annexes to the Turkish Food Codex Regulation on Microbiological Criteria specify different criteria and sampling methods to ensure the microbiological safety of foods.

Annex-1: Food Safety Criteria
This annex defines acceptable limits for pathogenic microorganisms and toxins likely to be present in foods placed on the market. Food safety criteria are used to determine whether food is safe at the point at which it reaches the consumer. For example, criteria such as that Salmonella spp. should not be present in certain foods are included in this annex.

Appendix 2: Hygiene Criteria
This annex contains criteria used to assess the effectiveness of hygiene practices in food production processes. Production hygiene criteria establish acceptable levels of certain microorganisms in production stages and ensure hygienic control of production processes. For example, this annex states that microorganisms such as Escherichia coli or Total Aerobic Mesophilic Bacteria Count must be within certain limits in certain foods.

Annex-3: Limits for Pathogenic Microorganisms
This annex is applied to detect microorganisms and their toxins and metabolites not included in Annex 1 for foods of doubtful safety and defined criteria are taken into account in the evaluation of the results obtained. The limits of pathogenic microorganisms defined in the Annex vary according to ready-to-eat and nonready-to-eat food samples.

Annex-4: Sampling and Analysis Methods
This annex provides guidance on how to sample food for microbiological analysis and which methods of analysis to use. Details such as sampling plans, frequency of analysis and specific microbiological test methods to be used are included in this annex. This ensures standardization of microbiological analysis and reliability of results.

By complying with these criteria, producers must protect consumer health and comply with international standards. Regular microbiological analysis is therefore an indispensable step for safe food production.

Why is Speed Important in Microbiological Analysis?

Speed is crucial in determining the presence of undesirable microorganisms in foods.

Detection of pathogens, especially those that can cause food poisoning, is vital for early intervention and protecting public health.
Lengthy testing processes to determine whether products are safe before they are put on the market can lead to delays in the production and distribution chain. With rapid testing, quality control can be ensured without disrupting production processes.
In particular, microbiological analysis of rapidly deteriorating foods such as milk, meat and fresh vegetables and fruits should be completed without shortening the shelf life of the products. Delays can lead to economic losses and spoiled products reaching the consumer.

How to Shorten Analysis Times?

Alternative rapid analysis methods can shorten analysis times. These methods include the use of culture media modified with specific enzymatic components or additional substances to support microorganism growth, or molecular-based instruments. Since specificity is generally increased in these analysis methods, the growth of the companion flora is effectively reduced, resulting in faster and more accurate detection of the targeted microorganism.

What are the Advantages of Fast Methods?

While traditional culture methods usually take 24-72 hours, rapid method analysis can give results in hours or minutes and time loss is prevented. Especially in analyzes with an incubation period of 5-7 days, such as Yeast and Mold Counts, results can be given in 48-72 hours with rapid method techniques.
The time to market of products is shortened and logistics processes become more efficient. Cost losses are reduced by preventing spoiled or contaminated products from being distributed.
Since rapid methods are usually molecular and immunologically based tests, they can detect specific pathogens more sensitively and accurately.
Even low-density microorganisms can be detected earlier compared to culture methods.

Why Nanolab?

As Nanolab Laboratories Group, we serve with a team specialized in food, feed and environmental samples and state-of-the-art equipment. We help you ensure food safety with both traditional and alternative fast methods in all analyzes included in the Turkish Food Codex Microbiological Criteria Regulation. You can contact us to learn more about all your microbiological analysis needs.

For more information, please contact us.
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