Studies on electrical properties of wheat bread as a function of moisture content during storage

Bread undergoes several physicochemical changes during storage that results in a rapid loss of freshness. These changes depend on the moisture content present in the bread product and collectively termed as staling. The present work explains how the electrical properties of bread vary with time and moisture content at its crust and crumb. An instrument based on electrical impedance spectroscopy with multichannel electrodes is developed for the present investigations. Detailed studies have been carried out to understand the influence of changes in moisture profile at bread crust and crumb in terms of electrical properties during the storage of 120 h. A linear relationship is observed between the measured impedance and capacitance and residual moisture content in bread at crust during storage. It is observed that the measured Resistance at bread crumb has a nonlinear mathematical relationship with moisture content present at crumb.