Hr. Lopes et al., SELECTIVE ENTEROTOXIN PRODUCTION IN FOODS BY STAPHYLOCOCCUS-AUREUS STRAINS THAT PRODUCE MORE THAN ONE ENTEROTOXIN, Journal of food protection, 56(6), 1993, pp. 538-540
Staphylococcus aureus strain S-6, producer of enterotoxins A and B-, s
train FRI-913, producer of enterotoxins A, C, and E; and strain FRI- 1
96E, producer of enterotoxins A and D, were grown in milk (pH 6.8), po
tato salad with mayonnaise, and boiled egg white (pH 8.0-8.5). Enterot
oxins were detectable in milk incubated at 26-degrees-C when colony co
unts were less than 10(6). Enterotoxin production by strain S-6 was de
tectable in potato salad at 10(6) CFU at both 26 and 37-degrees-C. Ent
erotoxin A production by strain FRI-913 was detectable at approximatel
y 10(6) CFU/g, whereas enterotoxin C was detectable only when growth r
eached approximately 10(8) CFU/g. Production of enterotoxins A and D b
y strain FRI-196E was detectable when growth was greater than 10(7) CF
U/g. Production of enterotoxins A and B by strain S-6 in boiled egg wh
ite was detectable at greater than 10(6) CFU/g. In most experiments, e
nterotoxins A and C from strain FRI-913 were detectable when cell coun
ts were greater than 10(7) CFU/g, whereas enterotoxin A and enterotoxi
n D production by strain FRI-196E was detectable at counts between 10(
5) and 10(6) CFU/g. It can be concluded that enterotoxin production is
influenced by the time of incubation and the composition and pH of th
e food.