Effects of PEF pre-treatment on vacuum microwave drying, freeze-drying, and hot air drying of Chilean abalone (Concholepas concholepas).

Gonzalez-Cavieres, Luis; Perez-Won, Mario; Palma-Acevedo, Anais; Jara-Quijada, Erick; Lemus Mondaca, Roberto A.; Diaz-Alvarez, Rodrigo

Keywords: freeze drying, hot air drying, PEF, Vacuum microwave drying

Abstract

The loco (Concholepas Concholepas) is a gastropod mollusk from the Muricidae family. It lives exclusively on the coasts of Chile and Peru; its meat is highly valued, has a high commercial price, and it is classified as a gourmet product. However, one of the main factors limiting export is its short shelf life. Currently, the drying of the loco is being studied as a method of preservation for export. In the present study, the processes of vacuum microwave drying (VMD) with a rotary system with 5 rpm speed, freeze-drying (FD) with a vacuum of 0.0021kPa and -55°C, and hot air drying (HAD) at 60°C, applying pulsed electric fields (PEF) as pretreatment (2kV cm-1), were investigated and compared in terms of drying kinetics, diffusivity, rehydration ratio, energy consumption, CO2 consumption, and loco microstructure. The VMD process was carried out in laboratory-scale designed equipment, using an initial power intensity of 7.74 W g -1 for 10 minutes and then 16.77 W g-1 with a vacuum pressure of 40kPa. The treatment that presented the highest diffusivity was VMD (3.28×10-9 m2s -1) and a processing time of 69 minutes; on the other hand, the treatment that presented the lowest diffusivity (7.30×10-10 m2 s-1 ) and the longest process time (9 h) was FD. Regarding energy consumption, there was a difference of 97% between FD and VMD; however, the FD rehydration ratio had the best results. Therefore, it is possible to conclude that both treatments have advantages that should be used according to requirements.

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Fecha de publicación: 2022
Año de Inicio/Término: Sep 20-21, 2022
Idioma: Ingles
Financiamiento/Sponsor: Universidad del Bio-Bio