Thermal and kinetic integrated models applied for Aspergillus fumigatus inactivation during ohmic and conventional juice pasteurization

Abstract

The integration of thermal and kinetic analysis of food processes is of great importance to compare and design different devices. Ohmic heating has been applied in food and beverage industry as an alternative to conventional pasteurization, aiming to provide a faster and more homogeneous heating process for fungi and bacterial inactivation. The objective of this study was to integrate differential Weibull models describing the death kinetics of Aspergillus fumigatus in apple juice with two different heating models to compare conventional and ohmic pasteurization. It was observed that ohmic heating presented shorter processing times in all conditions and, when comparing processes with the same duration and decimal reduction (5-log), the ohmic process was able to operate at temperatures from 5 to 10 °C lower. The results contribute to better understand the differences between ohmic and conventional technologies in terms of total processing time to guarantee the product microbiological safety. • Integration of kinetic and thermal models was used to study ohmic and conventional processing. • A 5-log reduction process was performed considering Aspergillus fumigatus inactivation. • For the same processing time, OH could operate at temperatures 5–10 °C lower. • In the absence of agitation, temperature was spatially homogeneous only in OH. • This study contributes to determine the pasteurization binomials in juice using CH and OH.