Unveiling Staphylococcus aureus enterotoxin production in dairy products: a review of recent advances to face new challenges

Staphylococcus aureus is a major food-borne pathogen worldwide and a frequent contaminant of foodstuffs where some strains are able to produce staphylococcal enterotoxins (SE). Consumption of foods containing these SEs is responsible for staphylococcal food poisoning (SFP) outbreaks. Milk and milk products are foodstuffs commonly associated with SFP. Typical SFP symptoms are vomiting with or without diarrhoea and abdominal cramping which reduce after 12 to 72 h. Despite extensive studies, the mechanistic base of SE production is still poorly understood but appears to be quite heterogeneous among the 21 different SEs identified to date. In this review, recent data regarding S. aureus and SE detection and quantification in dairy products as well as data about S. aureus growth and SE production with regard to parameters relevant for the dairy context and the cheese industry have been summarized. Recent technological developments have allowed the detection of S. aureus and SEs in foodstuffs to be refined. Similarly, molecular approaches have allowed high-throughput investigations of the physiology of S. aureus and revealed the complexity of this multi-faceted problem. SFP control must indeed take account of the growth of S. aureus as well as SE production. The wealth of new available data will open up new strategies for a better risk assessment and control of this major pathogen.