In this study, the working principles and the theoretical background of a new method to measure the viscoelastic properties of dough in the fermentation process are presented. During measurements, the dough sample was placed between a stationary bottom plate and an oscillating top plate and squeezed at random frequencies ranging from 10 to 100,000 rad/s. By measuring the required force and velocity of oscillations, the mechanical impedance of the samples, defined as the ratio of the force to oscillation velocity, was determined during fermentation. The measured mechanical impedance was used to calculate viscoelastic properties such as elastic and loss moduli of the dough samples. The nondestructive quick measurements and data covering a wide range of frequencies are some of the main advantages of the method. Furthermore, the described instrument can be easily affixed to the commonly available texture analyzer type equipments.