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13.02.2025 - Foods

New accredited rapid methods for the detection of pseudomonads and coagulase-positive staphylococci in food

Faster and Reliable Microbiological Analyses

We now offer accredited rapid methods for detecting Pseudomonas and coagulase-positive staphylococci in foods. These methods have been validated according to ISO 16140-2 against the ISO standard method and verified in our laboratory. The new procedures enable faster and reliable analytics with reliable and accredited results.

The rapid method for Pseudomonas provides robust results within 48 hours. The analysis of coagulase-positive staphylococci is completed within just 24 hours instead of the previously required minimum of two days. Since December 2024, these examinations have been performed in our laboratory.

Advantages of the New Rapid Methods:

• Results within a short time (Pseudomonas: 48 hours, Coagulase-positive Staphylococci: 24 hours)
• Accredited and validated procedures
• Increased planning reliability through quickly available results
• No additional costs
• Targeted analysis of Pseudomonas aeruginosa and Staphylococcus aureus upon request

Importance of Pseudomonas and Coagulase-positive Staphylococci in Foods

Pseudomonas are widespread in the environment and often found in foods such as fresh meat, fish, raw milk, as well as fruits and vegetables. Especially in products with high water content, they play a role as potential spoilage organisms.

In dry or vacuum-packed foods, their significance as spoilage organisms is lower, as they need water and oxygen to grow. In water hygiene, particularly Pseudomonas aeruginosa is of importance, serving as an indicator organism for contamination and biofilm formation. In medical facilities, this pathogen can also cause infections such as wound and urinary tract infections.

Coagulase-positive staphylococci, especially Staphylococcus aureus, are significant in food microbiology due to their ability to grow in foods under suitable conditions and produce toxins that can lead to food poisoning. These bacteria are often found in the environment, on the skin of humans and animals, as well as in various foods.

Key Causes of Increased Germ Count:

• Hygiene errors during production (e.g., contaminated equipment or insufficient personal hygiene)
• Processing of contaminated raw materials
• Cross-contamination between raw and processed foods
• Storage errors (too high temperatures, too long storage duration)
• Insufficient heating of foods
• For coagulase-positive staphylococci: High nutrient availability: Foods with high protein content (e.g., meat, dairy products) are particularly susceptible to growth
   

Growth Conditions of Pseudomonas:

• Temperature: 0 - 41°C
• pH value: at least 5.0
• aw value: at least 0.95
• Oxygen requirement: obligate aerobic

Growth Conditions of Coagulase-positive Staphylococci

• Temperature: Staphylococcus aureus grows best at temperatures between 30°C and 37°C. However, it can also survive at temperatures from 7°C to 48°C.
• pH value: The optimal pH range is between 4.0 and 10.0, with the bacterium thriving in slightly acidic to alkaline conditions.
• Water activity: These bacteria require a water activity (aw) of at least 0.85 to grow, which is the case in many foods.

Further Microbiological Analyses

In addition to these rapid methods, we offer a comprehensive range of microbiological tests, including:

Parameter                                         Testing Duration             Testing Principle                  Accreditation

Salmonella                                  1 day                  RT-PCR                  Yes
Listeria monocytogenes / Listeria spp.            6 hours                    RT-PCR                  No
Listeria monocytogenes / Listeria spp.                  1 day                      RT-PCR                  Yes
Cronobacter spp.                            1 day                  RT-PCR                  Yes
STEC/VTEC                                1 day                  RT-PCR                  Yes
Campylobacter spp.                          2 days                Cultural                Yes
Presumptive Bacillus cereus            1 day                  Cultural                Yes
Yeasts and Molds                3 days              Cultural                Yes
Lactic Acid Bacteria                  2 days                Cultural               Yes
Pseudomonas                           2 days                Cultural                Yes
Legionella                          6 hours                RT-PCR                No
Identification / Strain Comparison      2 to 24 hours        Maldi-Tof                Yes
 

About BAV Institut

BAV Institut is an accredited contract laboratory offering hygiene and quality control services to companies in the food, cosmetics, and pharmaceutical industries. In addition to laboratory testing, we specialize in practical consulting and training services.

With our modern laboratory and the high competence of our employees, we guarantee reliable and fast results. Other services offered by our institute provide valuable support to our customers. As a member of Tentamus Labs, we can offer you a wide range of tests nationally and internationally with the help of our partners.

Contact:

BAV Institut 

Dirk Lorenz
www.bav-institut.de 
dirk.lorenz@bav-institut.de
0781/96947-23