Application of High Pressure Processing After Freezing (Before Frozen Storage) or Before Thawing in Frozen Albacore Tuna (Thunnus alalunga)

Abstract

This work was focused on the application of high pressure processing (HPP) in frozen albacore tuna as a pretreatment before the frozen storage (BFS) or before thawing (BT) to minimize the negative effects of these conventional processes. Two different HPP pretreatments were evaluated (200/6: 200 MPa for 6 min; 600/0: 600 MPa for 0 min) and, after up to 45 days of frozen storage, thawing loss, color, texture, salt-soluble protein content, and lipid oxidation were analyzed once thawed. The application of HPP before thawing or before frozen storage reduced the thawing losses with respect to controls. For example, after 45 days of frozen storage, thawing loss of 600/0 BT and 600/0 BFS samples were 1.0 +/- 0.1\% and 1.8 +/- 0.2\%, whereas in the controls it was 5.0 +/- 0.4\%. After 45 days of storage, HPP BT samples presented lower thawing losses than the HPP BFS ones. Since non-important differences were detected in the rest of the studied parameters between both kinds of treatments, the application of HPP before thawing would be the best option. Regarding the tested HPP pretreatments, although 600/0 decreased thawing loss in a major extent than 200/6, this pretreatment led to sharp changes in color than 200/6 (higherL{*} andb{*} values) and texture (higher hardness and chewiness). Therefore, according to the results, the application of 200/6 BT would be a compromise option for reducing thawing loss in albacore with minimal changes on quality.