Effect of edible Fish gelatin coatings incorporated with ethanolic propolis extract on physicochemical, microbial and sensory properties of fish fillet (saurida tumbil) during storage at refrigerator

Fresh fish is a highly perishable product beacause of its biologic composition. In this regard, edile films and coatings are possible opportunities to prolong the shelf life of perishable food products such as fish fillets. The chemical composition of propolis – and, particularly, the wealth of bioactive compounds it contains– determines its application in food production.antimutagenic ve properties gelatin are biopolymers with preservative effect and film forming ability to from antimicrobial and antioxidant coatings and film.The aim of this study was to evaluate the effect of gelatin coating in combination with propolis (PE) on the microbiological (total mesophilic bacteria (TMB) and psychrotrophic (PTC) count), physicochemical (TVB-N, pH, TBARS, FFA) and sensory characteristics in Saurida tumbil fillets during refrigerated storage (4±1˚C). The results showed that the gelatin-PE samples reduced the extent of lipid oxidation, as judged by TBARS and FFA, suggesting that there is a synergistic effect between gelatin coating and propolis. Moreover, the application of gelatin coatings with PE improved the TVBN and pH values of the Saurida tumbil samples significantly compared to untreated sample, thus extending the shelf life of Saurida tumbil fillet approximately 4 days. Gelatin coating with PE was effective in inhibiting bacterial growth. The effect on the TVBN and pH indexes during storage was in accordance with bacterial activity. The gelatin-PE coatings had a positive effect in sensory acceptance of the fillets during storage. Thus, gelatin coatings enriched with PE had better impact on the sensory characterist/ics, and had more durability (4 days) than control. These results confirmed that gelatin coating enriched with PE can be an improving method to reducing deterioration of refrigerated Saurida tumbil fillets.Practical applications.

Keywords:

Saurida tumbil , Gelatin , Propolis , Shelf life