脱涩及1-甲基环丙烯处理对火柿贮藏期间电学特性的影响

Effects of deastringency and 1-methylcyclopropene treatment on the electrical properties of Diospyros kaki L. Huoshi during storage

中文关键词:  柿  电学特性  脱涩  1-甲基环丙烯

英文关键词:Diospyros kaki L. Huoshi  electrical properties  deastringency  1-methylcyclopropene

中文摘要:

      目的 明确脱涩与1-甲基环丙烯(1-methylcyclopropene, 1-MCP)处理对火柿贮藏期间电学特性的影响。方法 以火柿为材料, 分别利用高浓度短时CO2法进行脱涩, 用500 nL/L 1-MCP进行保鲜处理, 以未经处理的果实为对照(CK), 通过电感-电容-电阻(inductance-capacitance-resistance, LCR)阻抗分析仪测定室温贮藏期间各处理果实阻抗、电感、电容和电导在0.1、1.0、10.0、100.0和1000.0 kHz 5个频率下的动态变化。结果 火柿阻抗、电感随频率升高呈幂函数关系下降, 电导呈幂函数升高, 电容呈“先降后升”趋势; 贮藏期间, 各处理果实阻抗、电感呈线性关系下降, 电容、电导呈指数关系升高, 1.0 kHz为果实阻抗、电感和电容变化的敏感频率。1-MCP处理显著抑制了阻抗、电感的下降和电容、电导的升高速度, 1.0 kHz下, 贮藏24 d时, 阻抗、电感分别比CK高60.8%和59.7%; 电容和电导分别为CK的60.6%和44.6%。脱涩加剧了电学参数的变化速度和幅度, 第6 d时, 阻抗和电感分别较0 d时下降了88.9%和88.8%; 电容和电导分别为0 d时的9.2倍和15.4倍。结论 脱涩与1-MCP处理仅改变火柿电学参数变化的时间与幅度, 不改变变化模式; 电学参数对两种处理响应灵敏。本研究为无损检测柿果实的脱涩效果与耐贮性及1-MCP的保鲜效果提供参考。

英文摘要:

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