Effect of electrohydrodynamic pretreatment on drying rate and rehydration properties of Chilean sea cucumber (Athyonidium chilensis)

The objective of this study was to apply electrohydrodynamic (EHD) as a pretreatment, including several voltages and an application time of less than 1 h, combined with freeze drying (FD) to determine their influence on drying kinetics and drying rate, final moisture content, rehydration rate, and water absorption capacity, also, rehydration and water absorption capacity rates derived from the Weibull model. The best combination was compared with sun drying (SD) and FD. Initial drying rate increased because EHD influenced the moisture content on the product surface as exposure voltage increased. Rehydration and water absorption had a heterogeneous behavior, regardless of voltage. The 30 kV-30 min pretreatment had better drying kinetics and rate and was therefore compared with FD and SD, showing better results in the drying parameters. However, for rehydration before 2.5 h, FD behaved better. The Weibull model had a good fit to the experimental data for the three treatments. Crust formation was greater in the SD treatment, followed by EHD combined with FD, which was reflected in rehydration.