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The objectives of this research are to examine the effect of the electric field and magnetic field on the moisture content and water activity of bread. We studied how the electric field (0-8 KV), magnetic field (0-1400 mT) and treatment time (0-2 hrs.) affect the moisture content and water activity of bread. The effects of moisture content and water activity on bread were determined. Response surface methodology (RSM) based on three factor three level central composite design was applied to determine the effect of electric field level, magnetic field level and treatment time. A second-order polynomial model fitted well to the experimental data (R2=0.9854 and 0.9737) for moisture content and water activity, respectively. Significant moisture content and water activity were observed at the maximum treatment conditions of 8 KV of electric field, 1400 mT of magnetic field and treatment time 2 hrs., indicating stability of moisture content and water activity in bread. The main factor was electric field. The coefficients of moisture content were 0.2951 for electric field and 0.001579 for magnetic field. It was related with coefficients of water activity, which were 0.01159 and 0.000024 for electric field and magnetic field, respectively. The interaction of electric field and magnetic field was no significant for moisture content and water activity in bread.
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