Al. Mckay et al., THE GROWTH OF SALMONELLA-TYPHIMURIUM ON IRRADIATED, RAW, SKINLESS CHICKEN BREAST, International journal of food microbiology, 37(2-3), 1997, pp. 121-129
Salmonella typhimurium was inoculated onto 1 g cubed samples of irradi
ated, raw, skinless chicken breast, which were then incubated at 30 de
grees C under humid conditions. Kinetic growth data was obtained by me
ans of viable counts performed on triplicate samples over a 24 h perio
d. In addition, the spatial arrangement of cells on samples taken 6, 1
2 and 24 h after inoculation was observed by scanning electron microsc
opy. The population entered exponential growth approximately 3 h after
inoculation, and maintained a constant rate of growth for approximate
ly 13 h before entering a stationary phase. A generation time of 0.74
h was recorded. Scanning electron microscopy observations revealed col
onial development from loose clusters of cells at 6 h to discrete, com
pact microcolonies (approximately 40 mu m in diameter) by 12 h. By 24
h colonies were well-developed (approximately 600-700 mu m in diameter
) with a well-defined colony periphery. The results of this study give
insight into the growth and development of bacteria on meat tissue, a
nd serve to highlight that the nature of such growth is quite differen
t from that in dispersed liquid culture systems, i.e. those traditiona
lly used to model such growth. (C) 1997 Elsevier Science B.V.