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This study investigated the nonthermal effects of electricity on microbial inactivation kinetics of Staphylococcus aureus and Escherichia coli during ohmic heating (OH) of infant formula. For this, temperature profiles during OH and conventional heating (CV) processes were matched, and the kinetic parameters were compared at temperatures ranging from 57.5 to 65.0 8C. The inactivation kinetics were analyzed using an inactivation model, which allowed the definition of the thermal tolerance from k max and D values. For S. aureus, significant differences (p < .05) between D and k max values were observed when OH and CV treatment were compared in all temperatures. The results demonstrated a higher efficiency of OH over CV, indicating that microbial inactivation may have been caused by electroporation in addition to thermal effects. For E. coli, a significant difference (p < .05) between D values was observed only at 57.5 8C. Moreover, D values for both heating technologies were lower at 65 8C, which suggests a faster inactivation and, therefore, a lower degradation of nutritional compounds. Taking into consideration both microbial species, the best treatment for human milk pasteurization is OH at 65 8C. Practical applicationsThe low-temperature long-time pasteurization (62.5 8C for 30 min) is the currently recommended method for heat treatment of human milk in human milk banks (HMB) because it is simple to be applied and guarantees microbiological safety. However, it can promote significant losses of nutritional and organoleptic quality due to the slow conduction of heat transfer. Therefore, alternative technologies for human milk pasteurization need to be explored. OH is a faster heating technology, appropriate for heat-sensitive products. Although already established in the food industry, the OH advantages have not been considered for human milk pasteurization. The objective is to provide an alternative technology to the HMB that ensure safety and lower-impact on nutritional compounds. This study contributes for the correct understanding of the nonthermal effects associated with passage of electricity through foodstuff on microorganism's inactivation. Moreover, it has significant economic consequences to industry, supporting modeling and optimization to produce safe products with higher nutritional and sensory characteristics.

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