Efeito de revestimentos bioativos à base de quitosana sobre a vida útil e segurança da cavala (Scomberomorus cavalla) refrigerada

Abstract

Despite of the nutritional value, fish is one food with high chemistry instability and short shelf life. So, after his capture, it is recommended that fish will be stored as soon as possible under controled temperature. Temperature is a good method to maintain physical and chemistry properties of fish, however, now there are new methods or techniques able to improve its efficacy. Regarding that, the objective of this study was to evaluate the effect of bioactive coatings based on chitosan on shelf life and safety of Mackerel (Scomberomorus cavalla) refrigerated. In total, were used 80 samples of mackerel obtained from the Fish Market located at Mucuripe neighborhood, Fortaleza-CE. After being acquired, samples were placed in cool boxes and transported to the Meat and Fish Laboratory of Department of Food Technology, Federal University of Ceará, where they were stored at 4±1°C until to performed analysis. For evaluation of different treatment, samples were divided in groups, as following: C- Mackerel in nature; T1- Mackerel coated with chitosan + essential oil of oregano + ascorbic acid; T2: Mackerel coated with chitosan + ascorbic acid; T3: Mackerel coated with chitosan + essential oil of oregano; T4: Mackerel coated with chitosan. After the coating process by immersing, each set was placed in a polystyrene tray, wrapped in PVC film, labeled and stored at 4±1°C. After that, all analyzes were performed in triplicate every seven days and for 21 days. The results were submitted to analysis of variance (ANOVA) and Tukey test (p≤0.05), with the help of Statistica program Release 7. For the analysis of TVB and TMA, all treatments showed lower values than the control group. With respect to lipid oxidation, evaluated by TBARS was similar between groups. While all treatments were able to decrease the pH, theT4 showed more satisfactory results with respect to staining of the slices and Texture remains unchanged after different treatments. In turn, the microbiological analyses showed that T4 was also an effective treatment able to inhibit the growth of BHC and BPH in Mackerel samples maintained under refrigeration. Therefore, the chitosan-based coatings were effective to improve the shelf life of Mackerel, although there was not only one type of coating that has been effective protective role for all parameters.