High voltage electric field and vacuum freeze drying technology of sea cucumber

In order to improve the qualities of dried sea cucumbers, we tested two different drying processes that adopted both high-voltage electric field and vacuum freezing, namely, we dried the sea cucumber samples in a high voltage electric field for 3 h and 5 h, respectively, before drying them in the vacuum freezing condition. The drying effects of the two processes were compared with those of using only the high-voltage electric field drying or only the vacuum freeze drying, from aspects of the drying time, the energy consumption, the shrinkage rate, and the products’ rehydration rate, texture, protein content, and acid mucopolysaccharide contents. The results show that the two combined processes take less time and less energy than the single-stage drying process. The 3-hour and 5-hour treatment in electric field can save the electric energy required for vacuum freeze drying by up to 19.5% and 32.6%, respectively. Compared with the drying treatment with only high-voltage electric field, the combined processes improve the product quality, namely, the dried sea cucumbers with less shrinkage and hardness, higher rehydration capability, and more protein, can be produced.