Measurement of Fresh Tea Leaf Growth Using Electrical Impedance Spectroscopy

Electrical Impedance Spectroscopy (EIS) was applied to identify EIS parameters for the growth assessment of fresh tea leaves. We compared the EIS parameters of a distributed model with the dry matter content, which is a commonly applied parameter for growth assessment. As growth progresses, EIS parameters such as the relaxation time, resistances (except intercellular resistance) and dry matter content increased. According to the results of multiple linear regression analysis of the response surface model using fifty samples, the relaxation time displayed a good correlation with the dry matter content; however, the other parameters had no significant correlation. We concluded that the relaxation time would be useful for the growth assessment of tea leaves.