ISSN:
1745-4565
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Inactivation of Escherichia coli O157:H7 by pulsed electric field, benzoic or sorbic acid, alone or in combination was investigated. When the cells of E. coli O157:H7 were suspended in 10% glycerol and treated with a single highvoltage (12.5 kv/cm) electric pulse at 25C, the count decreased by 1.1–1.6 log10 CFU/mL. Presence of benzoic and sorbic acid (1000 ppm) in the suspending medium, at pH 3.4 without electric treatment, decreased the count by 1.9–2.5 and 0.6–1.1 log, respectively. A synergistic killing effect between the high electric pulse and organic acid was observed at pH 3.4, but not at pH 6.4. When the cell suspension of E. coli O157:H7 was treated with five electric pulses in the presence of benzoic or sorbic acid at pH 3.4, the count decreased by 5.6 and 4.2 logs, respectively. Inactivation of the pathogen by combinations of electric pulse and organic acid was enhanced by an increase in temperature, field strength, and number of electric pulses, Inactivation was greater when the cells were suspended in ionic suspending media (0.1% NaCl or 5mM phosphate buffer) than in nonionic media (10% glycerol or 1% sucrose).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1745-4565.1997.tb00169.x
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