Detection of cell membrane disruption using electrical impedance spectroscopy and acceleration of cell wall modification in carrot processed under low temperature blanching

In this study, we evaluated relationships between cell membrane damage and cell wall modification in carrots by low temperature blanching. Electrical impedance analysis was carried out to elucidate the tissue condition during low temperature blanching. The obtained parameters suggested that cell membrane disruption and electrolyte outflow was promoted by low temperature blanching at 60 °C than that at 50 °C. Low temperature blanching at 60 °C for 40 min showed greater softening inhibition than that at 50 °C. Meanwhile, the activity of pectin methylesterase at 60 °C was lower than that at 50 °C. Regarding cell wall condition, increased insoluble pectin and decreased water-soluble pectin were confirmed at 60 °C rather than that at 50 °C. To conclude, cell membrane disruption is assumed to trigger cell wall modification by exposing the cell wall and middle lamella to intracellular ions. •Electrical impedance analysis detected cell membrane damage and electrolyte leakage.•Intra- and extracellular resistance were changed dramatically by LTB at 60 °C.•LTB at 60 °C showed less softening after high-temperature heating.•Increased insoluble pectin was observed with the greater cell membrane damage.