Improving the microbial inactivation uniformity of pulsed electric field ohmic heating treatments of solid products

• DOI: 10.1016/j.lwt.2021.112709
• Publication Date: 2021-10-28T06:04:20Z
• Authors: L. Astráin-Redín; J. Moya; M. Alejandre; E. Beitia; J. Raso; B. Calvo; G. Cebrián; I. Álvarez
• Keywords: Electric heating; Ohmic contact

The application of Pulsed Electric Fields (PEF) at high frequencies leads to rapid and volumetric ohmic heating. Its in solid foods could avoid the problem conventional systems which external areas are over-treated order apply desired heat treatment center. In this study it was evaluated heating technical agar cylinders by applying PEF (2.5 kV/cm, 50 Hz) warming electrodes 25, 32 39 °C. Results showed that without control electrode temperature differences 10.5 °C after s. However, regulation reduced gradient 1.7 achieving 73.4 coldest point 28 To evaluate impact on uniformity microbial inactivation, inactivation Listeria monocytogenes STCC 5672 (D60°C = 0.63 min, z-value 5.4 °C) evaluated. inactivate 5-Log10 spot cylinder, 68 s were necessary when temperatures not regulated, 26 they tempered °C, reaching a 71