Effect of Farsi gum-based antimicrobial adhesive coatings on the refrigeration shelf life of rainbow trout fillets

- A double increase in the shelf life in the presence of EOs-loaded WFG coatings.
- No synergistic effect between Shirazi thyme and cinnamon essential oils.
- Increased antioxidant and antimicrobial activities by increasing EO concentration.
- Cinnamon essential oil was more effective than Shirazi thyme essential oil.

The present study aimed to evaluate the effects of antimicrobial and antioxidant adhesive coatings prepared from the water-soluble fraction of Farsi gum (WFG) on the refrigerated shelf-life of rainbow trout fillets. Antimicrobial and antioxidant characteristics were developed through incorporating cinnamon (CEO) and Shirazi thyme (SEO) essential oils, individually or in combination with each other. Coated fish fillets and control samples, stored at 4 ± 1 °C, were subjected to various microbiological (namely total viable count (TVC), psychrotrophic and lactic acid bacteria counts) as well as physicochemical (including peroxide value (PV), thiobarbituric acid reactive substances (TBARS), total volatile basic-nitrogen (TVB-N) and pH) evaluations during storage. Moreover, sensory characterisation were performed for texture, odour, colour and overall acceptability. Essential oils incorporation into WFG-based coatings had significant (p < 0.05) effects on decreasing total viable, psychrotrophic and lactic acid bacteria counts. The application of coating significantly (p < 0.05) reduced TVB-N, peroxide and TBARS values. Texture, odour, colour and overall acceptability of coated samples were much better than those of control samples. The results of this study showed that WFG could be used as a novel biopolymer source for introduction of EOs.