Abstract
During ohmic heating, the heating rate of a product depends on its electrical conductivity, a temperature dependent property. The electrical conductivity of the individual components in a multicomponent food system was determined over the entire sterilization temperature range (25−140°C). The product selected was chicken chowmein, composed of chicken, celery, mushrooms, water chestnuts, bean sprouts, and chowmein-style sauce. A device was developed to measure electrical conductivities of the components over the required temperature range. Results showed that the sauce (2.1 S/m at 27°C to 10.8 S/m at 140°C) was much more conductive than the solid components, i.e., celery (0.1 S/m to 3.4 S/m), water chestnut (0.1 S/m to 2.8 S/m), mushrooms (0.2 S/m to 1.4 S/m), bean sprouts (0.2 S/m to 1.5 S/m) and chicken (0.6 S/m to 3.4 S/m). Variation in electrical conductivity was also observed between different samples of the same component.
ACKNOWLEDGMENTS
Support provided by the USDA National Integrated Food Safety Initiative Grant No. 2003‐51110‐02093, titled: Safety of foods processed using four alternative processing technologies, is gratefully acknowledged. Salaries and research support provided in part by the Ohio Agricultural Research and Development Center, through the Regional Research Project NC-1023. References to products and trade names are made with the understanding that no endorsement or discrimination by The Ohio State University is implied.