1993 Volume 40 Issue 6 Pages 406-413
Sterilization of E. coli in foods under a high pressure was studied. E. coli cells cultivated at 37°C for 48h were used in this study, because they were more resistant to a high pressure than the younger cells. Samples in a nylon bag containing the 10 7-10 8 cells/ml were treated under 300MPa or 400MPa at 20°C for 10, 15 or 30min. E. coli was sterilized in any solution of water, 10-20% protein or 1-10% sucrose at pH 7.0-8.8 after 10min under 400MPa or at pH4.4-5.0 after 10min under 300 MPa. In the presence of more than 50% of soybean oil sterilization requires 15min under 400MPa, as opposed to the treatment for 10min under 400MPa with lard (solid oil). E. coli in a emulsion made by mixing an oil and a protein was needed to be sterilized under 400MPa for 30min. The most effect method for the sterilization was to treat bacteria solution frozen at -20°C under 200MPa for 10min.
