The procedure for the microbiological examination

Microbiological research example

The company is guided and advised by an external agency in the field of integral quality assurance. This external quality agency also carries out chemical and microbiological tests. The laboratory carries out its testing activities in such a way as to meet the requirements stated in the Dutch standard NEN-EN-ISO /IEC 17025. In this way, the needs of customers and legislative bodies are met. The laboratory has quality control procedures to monitor the validity of the tests that are carried out. The resulting data is recorded so that trends are noted and, to the extent practicable, statistical methods are applied to assess the results. This monitoring is planned and reviewed. This monitoring shall include the following:

• Regular use of certified reference materials and/or internal quality controls based on secondary reference materials.
• Participation in interlaboratory comparisons or proficiency testing programs.
• Repeat testing using the same or different methods.
• Re-testing or calibration of retained items.

The technical staff is dedicated to laboratory research. The technical employees are under the direct supervision of the management and are accountable for the work results achieved. The technical employees are engaged in making the technical capabilities of the company explicit. They are in conformity with the Dutch standard NEN-EN-ISO /IEC 17025 and ISO standards and comply with the quality instructions. The technical employees are sufficiently educated (HBO, WO) and have sufficient experience to perform the required analyses. Subject: Sampling and transport.

Sample Recording

It is important that the laboratory receive a sample that is a true reflection of the product. The sample should not be damaged or altered by transportation or storage. Sampling should not affect the existing microbial state of the product being sampled. For products in individual containers, this usually does not pose a problem. If the units are so large that they cannot be taken as samples in their entirety, a portion should be packaged in sterile material. In doing so, no more than three-quarters of the space should be filled so that spillage is avoided and the sample can be mixed properly for examination. Transfer is done aseptically with sterile tools so that contamination is avoided. If the tools are used several times in short succession at the sampling site, interim cleaning and sterilization is necessary. Instead of re-sterilizing tools, disposable sterile tools can also be used.

Transport

Transport should be performed correctly and quickly so that the number of microorganisms in the sample does not change during transport. The following storage temperatures should be used:

• Stable products: ambient temperature.
• Fresh and chilled products: between 0-4 degrees Celcius.
• Frozen or deep-frozen products: below -18 degrees Celcius.
• Pasteurized and related products: between 0-4 degrees Celcius.
• Perishable products: between 0-4 degrees Celcius
• Warning: sensitive foods (fresh fish) will need to be stored between 0-2 degrees Celcius. Perishables should be transported in sealed containers to protect them from leakage.

Sampling takes place with the inspection agency. Products are examined after production and at the end of the THT. All this is done with article 2073 as a guideline. The results are evaluated and any trends are examined. If certain products/product groups do not comply, improvement measures are taken:

• Product modification;
• Adjustments to recipe;
• Instructions hygiene;
• Adjustment of the production process;
• Modify raw and/or auxiliary materials.

If a sample is assessed as microbiologically insufficient, a counter sample is taken within 3 weeks. If this sample also deviates, the deviation is investigated and measures are taken. Water is tested 4 times a year. The water is examined for the following parameters, among others:

• Total germ count/ml at 22°C.
• Total germ count/ml at 36°C.
• Coliforms/100ml.
• Thermotolerant coliforms/100ml.
• Phaeacal enterococci/100ml.
• Traces of sulfite-reducing Clostridia/100ml A survey report is requested quarterly.

When applicable, challenge tests and “worst-case” tests are conducted in consultation with the research firm.

Manual check

Despite the fact that many production processes are automated, employee personal hygiene plays an important role in the preparation of a large number of food products. Often, contact with hands in production is unavoidable. Hands can be contaminated with microorganisms for various reasons. For example, the skin always contains skin-specific bacteria, the so-called residents. The most important representatives of this group are micrococci, staphylococci, propionibacteria and corynebacteria. In addition, hands are often contaminated from the outside through contact with the environment, the so-called transient contamination. These transients can originate from one’s own body (from the nose, mouth, pharynx or gastrointestinal tract) or from the environment in the broadest sense (other people, materials, pets etc.). The characteristic of transients is that they do not colonize (multiply) on the skin like residents, but can survive for a certain period of time. During that time, they can be re-transmitted to food via the hands. An exception is Staphylococcus aureus, which can colonize on the skin. Using the impression method, the presence of certain bacteria (e.g. Enterobacteriaceae, Staphylococcus aureus) on the hands can be examined. Calculate the number of CFU per 5 fingers. Frequency: 1x per 3 months. If the norm is exceeded, the handwashing procedure is discussed again with the person in question. After which re-sampling takes place. This is repeated until the desired results have been achieved.

Packaging

All packaging or packaging equipment is suitable for its intended use and has been tested for possible contamination and hazards (migration) to products and consumers. Effective and current test reports are available.

Organoleptic examination

In addition to microbiological testing, our products are tested for taste, color and odor. This is done after production and at the end of the shelf life. These tests provide insight into whether the products have the right quality requirements and continue to do so. In case of deviation, we try to find out the cause. This is done in case of repeated deviation of the counter samples. Based on the cause, measures can be taken for improvement:

• Adjusting recipe;
• Adaptation of raw materials/resources;
• Adjustment of production process.

Glove control

From each batch of gloves, 5 gloves are checked for any leakage and for appearance. If correct, the products are released for use. In case of deviations, the products are returned to the supplier.

Assessment of research results

Assessment of the examination results should be recorded. At our company, all sample results are found to be okay unless an abnormality is found. This is specifically named and action is taken in response to the result. Actions may include:

1. Verification by laboratory to method of testing (in case of odd results);
2. Correction to product, where possible;
3. Corrective action to product, process, production area and personnel.
4. If necessary, this process can be reported via iMIS audit.

More about Audit system.