关键词: 猕猴桃, 损伤, 电特性, 敏感电参数

Abstract: In this experiment, the post-harvest fruits of kiwifruit cultivar  Hayward  were selected to create a damage model through free-fall movement from a height of 50 cm. An intelligent LCR Hioki tester was used to determine changes in 6 electrical parameters of fruits such as complex impedance (Z), parallel equivalent capacitance (Cp), parallel equivalent inductance (Lp), loss coefficient (D), conductance (G) and impedance phase angle (θ) at electric shock frequencies of 100, 158, 251, 398, 631 kHz and 1000 kHz with the extension of storage time. Results indicated that both damaged and control fruits presented a decrease trend of Z and Lp, an increase trend of Cp and G, an initial increase and then final decrease of D, and an initial decrease and then final increase of θ as electric shock frequency increased at (25 ± 1) ℃. The complex impedance Z at 6 selected electric shock frequencies in damaged fruits was much lower than that in undamaged fruits. Therefore, the parameter can distinguish damaged and healthy fruits as a sensitive electrical parameter. Meanwhile, a significant difference in loss coefficient D between impaired and healthy fruits was determined at electric frequencies of 100 kHz and 251 kHz. As a result, both fruit impedance Z and loss coefficient D can be chosen as an electronic indicator for kiwifruit impairment.

Key words: kiwifruit, damage, electric property, sensitive electrical parameter