Effect of microbial control measures on farmstead cheesemaking and antimicrobial resistance of Staphylococcus aureus and Enterococcus spp. isolates

Abstract

AbstractThe effect of microbial control measures in farmstead cheese making was evaluated in a small dairy farm in Gyeong‐gi province, Korea. Teat washing and pasteurization significantly (p < .05) reduced the level of indicator bacteria (mesophilic aerobes, total coliforms, and Escherichia coli). However, farmstead cheeses were contaminated with increased levels of mesophilic aerobes, total coliforms, Staphylococcus aureus, and Enterococcus faecium during post‐pasteurization steps, including the cheesemaking process and ripening. S. aureus isolates from cheese samples exhibited antibiotic resistance to penicillin/ampicillin, whereas teat and milk samples showed resistance to erythromycin/ciprofloxacin. Enterococcus spp. isolates had the highest proportion of organisms resistant to erythromycin and tetracycline among multidrug‐resistant strains. To ensure the safety of farmstead cheese, customized management systems and intervention methods should be established by focusing on control measures for not only preprocessing and pasteurization but also post‐pasteurization steps.Practical applicationsOwing to renewed interest in specialty cheeses, small‐scale farmstead cheeses are actively produced worldwide. However, because of various manufacturing steps, including milking, pasteurization, ripening, and storage, farmstead cheese could pose a high risk for the presence of foodborne pathogens. In the current study, teat washing and milk pasteurization effectively reduced microbial contamination loads. However, farmstead cheeses were contaminated post‐pasteurization with increased levels of indicator and pathogenic microorganisms. Comprehensive management systems should be implemented and should focus not only on preprocessing and pasteurization but also on post‐pasteurization steps to ensure the safety of farmstead cheese.