In this study the thermal resistance of seven strains of staphylococci was studied. Three of them (two
Staphylococcus epidermidis and one Staphylococcus lugdunensis) were isolated from pasteurized tofu,
while one Staphylococcus aureus from fermented sausages. Also the corresponding type strains were
tested. Their heat resistance was assessed at 80 C also in relation to different growth conditions (high
NaCl concentrations and low pH). Moreover, the effect of two terpenes (carvacrol and citral) on their
survival during thermal treatment was assessed. All the strains were able to survive a 20 min thermal
treatment and showed a similar behavior, i.e. an inactivation of about 6 log units in the first 2e4 min of
treatment, followed by constant survivor counts (2e4 log CFU/ml). The pre-culture of staphylococci
under stressing conditions (high NaCl concentration and low pH) increased the susceptibility to thermal
treatment in three strains isolated from food matrices. The addition of carvacrol and citral during thermal
treatment influenced the number of survived cells at the end of the treatment. This new insight in the
thermal resistance of staphylococci needs to be better investigated, in order to study proper strategies to
control their occurrence and behavior in real food systems.