Influence of Fall Height and Storage Time on Dielectric Properties of Red-Globe Grape

The changes of dielectric parameters of the red-globe grapes which fell from various heights and then were stored 3d,6d,10d in room temperature were studied with parallel plate capacitor method in the rang of 50Hz-1MHz. With the increase of frequency, the complex impedance mould and relative dielectric constant is decrease, conductance is increase, loss factor is first decrease then increase and quality factor is first increase then decrease. With the increase of height, the complex impedance and quality factor is first increase then decrease, conductance, relative dielectric constant and loss factor is first decrease then increase in the height range of 80-200cm. In the fall height of 120cm, the complex impedance and quality factor is maximum value, and conductance, relative dielectric constant and loss factor is minimum value. With the increase of storage time after red-globe grapes fall from the height of 120cm, the complex impedance and quality factor is decrease, and conductance, relative dielectric constant and loss factor is increase.