The trehalase activity plays an important role in extraction of trehalose from beer yeast. In this study, the
effect of pulsed electric field processing on neutral trehalase activity in beer yeast was investigated. In
order to develop and optimize a pulsed electric field (PEF) mathematical model for activating the neutral
trehalase, we have investigated three variables, including electric field intensity (10–50 kV/cm), pulse
duration (2–10 s) and liquid–solid ratio (20–50 ml/g) and subsequently optimized them by response
surface methodology (RSM). The experimental data were fitted to a second-order polynomial equation
and profiled into the corresponding contour plots. Optimal condition obtained by RSM is as follows:
electric field intensity 42.13 kV/cm, liquid–solid ratio 30.12 ml/g and pulse duration 5.46 s. Under these
conditions, with the trehalose decreased 8.879 mg/L, the PEF treatment had great effect on activating
neutral trehalase in beer yeast cells.