Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6394149 | Food Control | 2012 | 7 Pages |
The combined effect of the simultaneous application of heat and ultrasonic waves under pressure (manothermosonication, MTS) on the survival of a strain of Cronobacter sakazakii was studied in apple juice. Below 45 °C, the inactivation by ultrasound under pressure was independent of temperature. Above 64 °C, the lethal effect of ultrasound under pressure was negligible when compared to the lethality of the heat treatment at the same temperature. Between 45 °C and 64 °C, the lethality of the combined process (MTS) was higher than expected if heat and ultrasound under pressure processes acted simultaneously but independently, that is, a synergistic effect was observed. The maximum synergistic effect (38.2%) was found at 54 °C. Recovery on selective media - with sodium chloride or bile salts - revealed that a certain proportion of the survivors after MTS treatments were sublethally injured. It was also observed that survivors after MTS treatments progressively died during refrigerated storage (up to 96 h at 4 °C) in the apple juice. The practical implication of these findings is discussed.
⺠The combination of heat and ultrasound was synergistic between 45 and 64 °C. ⺠Damaged cells were found after heat and MTS treatments. ⺠Survivors to MTS treatments died during refrigerated storage in apple juice.