Fundamental Food Microbiology, Third Edition - Fuad Fathir

100 FUNDAMENTAL FOOD MICROBIOLOGY
Table 8.1 Germination Induction of Bacterial Endospores by Hydrostatic Pressure at
25 and 50����C
Bacterial
Strain
Bacillus cereus
ATCC 10876
Bacillus
stearothermophilus
ATCC 12980
Clostridium sporogenes
PA 3679
Clostridium perfringens
ATCC 1027
Pressurization
for 5 min at
Temperature (����C)
when they cause spoilage and produce toxins (except yeasts) in food and can be
desirable in the processing of some foods. Methods of destruction of spores and
inhibition of germination of spores (of bacteria) by different means are used to
control their growth in food.
Some bacterial species sporulate as a means of survival strategy under conditions
of physical, chemical, or environmental stresses by genetically regulated processes.
Cells of many bacterial species, when exposed to conditions suboptimal for growth
or sublethal, manifest different characteristics, the control mechanisms of which are
not properly understood currently. These conditions are observed with many foodborne
bacteria and have important implications in food microbiology, which are
discussed in Chapter 9.
REFERENCES
% Germination Induction a at MPa b
138 345 483
25 99 99 99
50 99 99 99
25 45 88 88
50 99 98 98
25 0 0 4
50 40 50 82
25 17 21 29
50 12 40 44
a The spore suspensions were pressurized for 5 min either at 25 or 50�C, then stored at 4�C
for 1 h and heated at 75�C for 15 min to destroy the germinated spores. Germination induction
was determined by enumerating the surviving spores and subtracting the number from the
unpressurized (control) spore suspensions.
b MPa: MegaPascal (1 MPa = 145 psi)
1. Gould, G.W., Ed., Germination, in The Bacterial Spores, Academic Press, New York,
1969, p. 397.
2. Gombas, D.A., Bacterial sporulation and germination, in Food Microbiology, Vol. 1,
Montville, T.J., Ed., CRC Press, Boca Raton, FL, 1985, p. 131.
3. Sneath, P.H.A., Ed., Endospore-forming Gram-positive rods and cocci, in Bergey's
Manual of Systematic Bacteriology, Vol. 2, Williams & Wilkins, Baltimore, 1986,
p. 1104.