Effect of CarboxyMethyl Cellulose Edible Coating enriched with Satureja hortensis Extract on the Biochemical, Microbial and Sensory Characteristics of Refrigerated Lethrinus nebulosus Fillets

In this study, the effect of carboxylmethyl cellulose edible coating containing summer savory (Satureja hortensis) extract on the quality of Lethrinus nebulosus fillets during chilled storage was evaluated. Summer savory extract was extracted using ethanol 80% and its chemical compositions was analyzed using GC/MS system that totally 22 compounds were detected for summer savory extract and carvacrol was the main compound (28.67%) of extract according to GC/MS analysis. The fish fillets were divided into five groups: the control, CMC and CMC coating containing 0.5, 1 and 1.5% of summer savory extract and stored at 4±2°C for 9 days. During storage period, the analysis of biochemical (pH, TVB-N, TBA and FFA), microbial (total viable count and psychrotrophic count) and sensory evaluation (texture, odor, color and overall acceptance) for all samples were showed significantly changes (p<0.05). At the end of storage period, the sample treated with 1.5% of extract significantly had the lowest values of TBA, FFA and microbial growth compared to the control (p<0.05). Also, coated samples had the lower values of pH (p<0.05) and TVB-N than the control sample at the end of storage period. As regards to sensory evaluation, the coated samples had a longer shelf life (3 days) than the control sample, and the sensory properties of samples treated with extracts of 1 and 1.5%, significantly improved compared to the control on day 9 (p<0.05). Therefore, CMC coating enriched with summer savory extract represents a promising method for maintaining the quality of L. nebulosus fillets during chilled storage.