To clarify the effects of deastringency and 1-methylcyclopropene (1-MCP) treatments on the electrical properties of Diospyros kaki L. Huoshi during storage.

High-concentration short-term CO₂ treatment was applied to Diospyros kaki L. Huoshi for deastringency, and 500 nL/L 1-MCP was used for preservation, respectively, with untreated fruits as the control (CK). Inductance-capacitance-resistance (LCR) impedance analyzer was employed to determine the dynamic changes of impedance, inductance, capacitance and conductance of the treated fruits at 5 frequencies (0.1, 1.0, 10.0, 100.0 and 1000.0 kHz) during room-temperature storage.

The impedance and inductance of Diospyros kaki L. Huoshi showed a power function decrease with increasing frequency, while conductance increased in a power function pattern, and capacitance exhibited a slow decrease followed by fast increase manner. During storage, the impedance and inductance of fruits in all treatments decreased in a linear relationship, and capacitance and conductance increased in an exponential relationship. The frequency of 1.0 kHz was the sensitive frequency for changes in fruit impedance, inductance and capacitance. The 1-MCP treatment significantly inhibited the decrease rate of impedance and inductance, as well as the increase rate of capacitance and conductance. At 1.0 kHz, after 24 d of storage, the impedance and inductance of 1-MCP treated fruits were 60.8% and 59.7% higher than those of the CK, respectively; while the capacitance and conductance were 60.6% and 44.6% of those in CK, respectively. Deastringency accelerated the changing process of electrical parameters: On the 6th day, the impedance and inductance decreased by 88.9% and 88.8% compared with 0 d, respectively; the capacitance and conductance were 9.2 and 15.4 times those on 0 d, respectively.

Deastringency and 1-MCP treatments only alter the time and amplitude of electrical parameter variations in Diospyros kaki L. Huoshi persimmon, but not the pattern;the electrical parameters are sensitive to above 2 kinds of treatments. This study provides a reference for the non-destructive detection of deastringency efficiency and storability and 1-MCP preservation effect of persimmon fruits.