The Effect of Sublethal Heat Treatment on the Growth of Staphylococcus aureus

S ummary : When an enterotoxigenic strain of Staphylococcus aureus was subjected to sublethal heat treatment and subsequently inoculated into nutrient broth and incubated at 37° there was a fall in viable numbers. This fall was followed by a lag phase of growth. When the sublethally heated organisms reached the logarithmic phase of growth they showed the same doubling time as unheated organisms. The maximum numbers of organisms reached in nutrient broth was generally the same for heated and unheated organisms. The fall in viable numbers and the delayed lag phase are discussed.