Conclusions
-
1.
Exposure of nine different strains ofStaphylococcus aureus in broth to heat treatments up to 5 minutes at 121°C. was found not to alter the Gram reaction of the cocci, neither immediately nor after subsequent storage during 14 days at 5°C.
-
2.
When the same strains were inoculated into canned spinach stew, they showed again no difference in Gram reaction when heated to F>2.6, neither in the fresh product nor after subsequent incubation for 10 days at 32°C.
-
3.
A heat treatment lethal toStaphylococcus aureus but not inactivating its enterotoxin has therefore no influence on the stainability of staphylococci. Hence a bacterioscopic examination of such products as suggested byMossel andZwart (1959) may reveal potentially dangerous pre-process development of staphylococci.
Similar content being viewed by others
Literature
Angelotti, R., Foter, M. J. andLewis, K. H. 1961. Applied Microbiol.9, 308.
Dack, G. M. andSurgalla, M. J. 1953. Food Technol.7, 307.
Moats, W. A. 1961. J. Dairy Sci.44, 1431.
Mossel, D. A. A. andZwart, H. 1959. Arch. Lebensm. Hyg.10, 229.
Author information
Authors and Affiliations
Additional information
This investigation was carried out during a study period spent by the author at the Institut National pour l'Amélioration des Conserves de Légumes (INACOL), Wezembeek, Belgium.
Rights and permissions
About this article
Cite this article
Kvåle, O. The influence of heat treatment on the gram stain of pathogenic staphylococci. Antonie van Leeuwenhoek 28, 365–368 (1962). https://doi.org/10.1007/BF02538748
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02538748