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21.04.2023 - Foods
CVUA: Microbiological Examinations of Raw Milk from Vending Machines from 2020 to 2022
In the period from 2020 to 2022, the Chemical and Veterinary Investigation Office (CVUA) Stuttgart examined a total of 54 raw milk samples from milk vending machines, primarily focusing on their microbiological quality. In addition to the total bacterial count, spoilage and hygiene bacteria, the presence of pathogenic bacteria such as Salmonella, Campylobacter, Shiga- or Verotoxin-producing E. coli (STEC/VTEC), and Listeria monocytogenes was also checked. In 44% of the samples, noticeable results were observed, with several parameters being elevated or too high per sample.
Total bacterial content, spoilage and hygiene bacteria:
- 24.5% showed an increased total bacterial count (>1.0x10^5 CFU/mL)
- 30.8% contained spoilage-inducing Pseudomonas with a content of >10^4 CFU/mL
- In 24.5%, the bacterial content of Enterobacteriaceae, classified as hygiene bacteria, was >10^3 CFU/mL
- The fecal indicator bacterium Escherichia coli was detected in 9.4% with a content of >10^2 CFU/mL
- S. aureus was found in 17.3% with bacterial counts of >10^2 CFU/mL
Pathogenic bacteria:
- Salmonella and Campylobacter were not detected in any of the 54 samples tested
- 12.9% showed the presence of Shiga- or Verotoxin-producing E. coli (STEC/VTEC)
- In 5.6%, L. monocytogenes was qualitatively detected in 25 g, with bacterial content predominantly below the detection limit of 10 CFU/mL
Since raw milk is not subjected to any special heating or germ reduction procedures, it can contain pathogenic bacteria. Hygienic deficiencies at the production site (poor cleaning condition of milking machines, pipes, and tanks) or inadequate and incomplete cooling can also lead to contamination of raw milk with spoilage and hygiene bacteria (Pseudomonas, Enterobacteriaceae) after milking. Existing pathogenic bacteria (Salmonella, Campylobacter, L. monocytogenes, S. aureus, STEC, or VTEC) are rendered harmless by heating, which significantly reduces the risk of infection.
Particularly at-risk groups, such as young children, pregnant women, the elderly, and ill individuals, are generally advised against the consumption of raw milk without prior boiling and raw milk products.
In our Tentamus laboratories, we regularly conduct the mentioned microbiological tests. We provide you with fast and reliable results.
Our customer advisors are always available to answer your questions.
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