Modelling of Salmonella Enteritidis inactivation in liquid whole egg under dynamic manothermosonication treatments

Manothermosonication (MTS) is a potential alternative to traditional thermal pasteurisation of liquid whole egg (LWE), aiming at a lower thermal load than in the thermal treatment, and thus may less affect the food quality while delivering microbiological safety. In this study, the inactivation kinetics of Salmonella Enteritidis DSM 17420 in LWE under (dynamic) MTS conditions was modelled, and MTS's synergistic lethal effect considering ultrasound and thermal treatments independently at static (isothermal) and non-static conditions was evaluated. Results showed that the inactivation of S. enteritidis DSM 17420 by MTS followed a first-order inactivation kinetic, and the log-linear model was applied successfully to obtain the Dref-, zT-, and zUI-values, being 1.12 ± 0.01 min, 22.93 ± 0.02 °C, and 692.52 ± 0.02 W/cm2, respectively, at the reference conditions of 57 °C and 166.91 W/cm2. The synergistic lethal effect of MTS was confirmed by comparing the Dref-values obtained for ultrasound (13.03 ± 0.39 min) and dynamic thermal treatments (5.56 ± 0.23 min). Manothermosonication has the potential to pasteurise liquid whole egg achieving the same safety level of Salmonella Enteritidis inactivation as traditional heat-based pasteurisation with lower thermal load, which may result in the preservation of food quality. However, further studies are needed to evaluate the effect of manothermosonication on the functional properties of liquid whole egg.