The effect of the combined use of high pressure treatment and antimicrobial edible film on the quality of salmon carpaccio

Abstract

Fish carpaccio is a ready-to-eat product with a very limited shelf life. In the present work, the use of high pressure treatment (HP) and/or antimicrobial edible film was studied in order to improve quality and stability of salmon carpaccio. In a preliminary part of the work, a film composed of gelatin plus chitosan incorporating clove essential oil was selected, based on its physicochemical and antimicrobial properties. Eugenol and β-caryophyllene, the main volatile components of the film, migrated to salmon muscle, the release being favored by HP and storage time. Concurrently, reducing power of the muscle increased, resulting in prevention of lipid oxidation derived from either HP or refrigerated storage. HP treatment reduced total microbial counts by 1.5 log cycles from the onset of storage, whereas the film reduced it by 2 log cycles after 3 days. The combination of HP and edible film exerted the most intense antimicrobial effect, total bacterial counts, luminescent bacteria, H₂S-producing organisms, pseudomonads, enterobacteria, and lactic acid bacteria remaining constant or under detection limit over the whole storage period (11 days). The combined use of HP treatment and gelatin-chitosan-clove essential oil film is an effective way of improving quality and stability of salmon carpaccio.

Keywords: Chitosan; Clove; Gelatin; Shelf life; Volatile compounds.