Quality Enhancement of Chilled Lean Fish by Previous Active Dipping in Bifurcaria bifurcata Alga Extract

The present study addressed the quality enhancement of chilled fish by applying a preliminary dipping treatment containing a bioactive extract of the alga Bifurcaria bifurcata. Megrim (Lepidorhombus whiffiagonis) specimens were dipped in ethanolic-aqueous solutions containing two different concentrations of the alga extract (high: HAC batch and low: LAC batch). Two types of control batch were considered (ethanol-water dipping and no dipping). Microbial, chemical and sensory qualities were monitored in fish throughout a 13-day storage period. An inhibitory effect (p < 0.05) of the dipping treatment (washing and the presence of alga extract) on microbial activity was observed, as determined by microbial (Enterobacteriaceae, lipolytic bacteria and psychrotrophs) and chemical (trimethylamine and free fatty acid formation) analyses. In most cases, this effect was found to be more intense for prolonged storage times and in fish specimens corresponding to the HAC batch. However, the combined effect of washing and the inclusion of alga extract in the dipping medium did not affect (p > 0.05) the rate of lipid oxidation events during storage. Interestingly, average scores revealed increased sensory quality in megrim corresponding to the HAC batch for prolonged storage (9-13 days). Consequently, the use of a bioactive extract of B. bifurcata alga as a preliminary dipping treatment can be considered of interest for further fish storage due to both its simplicity and beneficial effects on fish quality enhancement.