Occurrence of Staphylococcus aureus on Farms with Small Scale Production of Raw Milk Cheeses in Poland

Abstract

This paper describes the results of a 3-year study on the prevalence, enterotoxinogenicity and resistance to antimicrobials of S. aureus isolated on dairy farms with small scale production of raw cow milk cheeses. The samples of raw milk, semi-finished products and the final products as well as swabs were collected between 2011 and 2013 from nine dairy farms in Poland. A total of 244 samples were examined, of which 122 (50.0%) were contaminated with S. aureus including 18 of 26 (69.2%) mature cheese samples with log10 CFU g−1 between <1- and 7.41. In swabs collected from the staff and production environment the highest contamination rate with coagulase positive staphylococci (CPS) was detected on hands of cheese makers (4.34 log10 CFU/swab). None of the cheese samples contaminated with CPS contained staphylococcal enterotoxins (SEs). However, 55 of 122 (45.1%) S. aureus isolates possessed SEs genes, mainly (26 of 55; 47.3%) a combination of the sed, sej and ser genes. Furthermore, the sep (15 of 55; 27.3%) as well as seg and sei (9 of 55; 16.4%) genes were also identified. The remaining S. aureus isolates possessed the sea gene (one isolate), the combination of sec, seg and sei (three isolates) as well as the sed, sej, sep and ser markers together (one CPS). Resistance to penicillin (62 of 122 isolates; 50.8%) was the most common among the tested isolates. Some CPS were also resistant to chloramphenicol (7; 5.7%) and tetracycline (5; 4.1%). The obtained results indicated that the analyzed cheeses were safe for consumers. To improve the microbiological quality of traditional cheese products more attention should be paid to animal welfare and hygiene practices during the process of cheese manufacturing in some dairy farms.

Bacterial Communities in Serpa Cheese by Culture Dependent Techniques, 16S rRNA Gene Sequencing and High‐throughput Sequencing Analysis

“…aureus was only found in cheeses from industry V (non-PDO registered) (Table 3). In raw milk cheese, S. aureus contamination can be caused by raw milk produced by animals suffering from mastitis, contaminated milk tank, and poor hygiene practices or the cheese handlers who are S. aureus carriers (Guerreiro, Velez, Alvarenga, Matos, & Duarte, 2013;Rola, Czubkowska, Korpysa-Dzirba, & Osek, 2016). S. aureus has been reported in cheese made from raw milk with a higher incidence than other foodborne pathogens (Little et al, 2008;Ordiales et al, 2013a).…”

Detection of Enterotoxigenic Staphylococcus aureus Strains in Raw Milk of Cows Reared in Erbil Province/Iraq

“…The high proportion of enterotoxin producers among S. aureus compel the preservation of the cold chain to inhibit the synthesize of the S. aureus stable enterotoxins (Hennekinne et al, 2012). The techniques that are used, the geographical regions and the origin of the isolates describe the difference in the prevalence of enterotoxin production (Riva et al, 2015, Rola et al, 2016.…”

Microbiological Safety of Various Gouda Cheeses Produced from Raw Milk

“…원유에서 0.5∼6.1% 그리고 치즈에서 0.5∼4.3% 정도 Salmonella가 검출되었다 (Almeida et al, 2007;Ahmed and Shimamoto, 2014). 일반적으로 독소를 생산하기 위해서는 최소 10 5 CFU/g 이상의 S. aureus는 균체가 존재하여야 하며, 만약 이 독소를 사람들이 섭취하였을 때 식중독을 유발하는 병원성 세균이다 (Rola et al, 2016). 특히 S. aureus는 사람의 손, 코 점막, 타액 등에 주로 존재하 기 때문에, 작업자들에 의해 원유 및 치즈에 상호 교차오염될 수 있어 특별한 주의가 요구되며, 다른 세균들보다 S. aureus는 원유에서는 46.2∼73.5%, 치즈에서는 6.3∼75%로 높게 검출되었다 (André et al, 2008;Kiros et al, 2016;Rola et al, 2016;Lee and Yoon, 2017 (Anfossi et al, 2012).…”