Abstract

The Chilean abalone is a gourmet product of high commercial value both in Chile and in the world. Hence the use of freeze-drying is presented as an interesting alternative for its commercialization. The objective of this study was to evaluate different magnitudes of pulsed electric fields (PEF) in the digestibility and the freeze-drying process of Chilean abalone. The experiments were carried outby applying PEF (0.5, 1.0 and 2.0 kV cm-1) to sheets of Chilean abalone, and it was subsequently cooked (CO). Another group of Chilean abalone sheets was cooked, and then PEF was applied. Both groups were freeze-dried. As a control sample, fresh Chilean abalone sheets were freeze-dried. The kinetics and diffusivity of the freeze-drying process, protein content, degree of hydrolysis (DH), Computer-Protein Efficiency Ratio (C-PER), Differential Scanning Calorimetry (DSC), and Fourier Transformed Infrared Spectroscopy (FT-IR) were evaluated. The result for diffusivity shows that a lower value of 7.30 × 10−10 m2s-1 was obtained for the control sample. The treatment that presented the shortest freeze-dried time and the highest C-PER was the sample 2.0 PEF. Regarding DH, there were only significant differences at minute 90 of the process. Finally, it is important to mention that the amide I region of the proteins was affected by all the treatments, as well as the general structureresults for DSC analysis. In conclusion, the order in which the treatments were applied affected thestructure of the Chilean abalone proteins. Finally, it is possible to say that PEF could generate new perspectives on the freeze-drying process and protein digestion.