White cheese has been involved in many staphylococcal food poisoning o
utbreaks in Minas Gerais State, Brazil. Experiments were conducted to
determine at what stage in the making of white cheese is the enterotox
in produced that is the cause of staphylococcal food poisoning. Pasteu
rized milk was inoculated with 10(2) and 10(4) cfu/ml of an enterotoxi
n A-producing Staphylococcus aureus strain and incubated at 26-degrees
-C-27-degrees-C for varying lengths of time before making the cheese.
The milk, samples of the curd, and day-old cheese were used for determ
ining staphylococcal count and the presence of enterotoxin. No enterot
oxin was detectable in the cheese made from the milk inoculated with 1
0(2) Cfu/ml. Enterotoxin was detectable in the cheese curd made from t
he milk inoculated with 10(4) cfu/ml after it had been held for 5 hour
s and was present in all cheese samples.