Analysis of energy and exergy in the ohmic process during cooking: a case study of button mushroom

Ohmic heating is a fast and uniform heating and produces a high-quality product with minimal changes in structural and nutritional properties, and it is also an environmentally friendly method that has been considered due to its beneficial properties. In this study, an ohmic processing system was developedthat used three independent factors such voltage gradients, electrode type (steel, brass and aluminum) and concentration of ohmic solution for mushroom cooking. Some factors for device had calculated such energy efficiency, exergy efficiency and exergy loss during the cooking and all data analyzed by SAS statistical program. The results showed that all independent factors had significant meaning on mushroom cooking. The highest significant was for voltage gradient and after this factor, electrode type and concentration of ohmic solution had the high amount for energy efficiency, exergy efficiency and exergy loss. The highest energy efficiency was equal to 79.57 joules, and the exergy efficiency was 61.36 joules, observed in the steel electrode and at a voltage gradient of 11.25. The highest amount of exergy loss was 39.6 at a voltage gradient of 5.7 and with the aluminum electrode. Based on results, it can be stated that the best type of electrode used was steel electrode and concentration 2 showed the best values.