M.A. Thesis:

performance of edible coating based of whey protein concentrate containing of aqueous extract of saffron (crocus sativus) petals extracted by ultrasound assistance of shelf - life ٫ physicochemical and sensory properties of Iiranian salmon fish fillet during refrigerated storage.

In this research, the process of shelf-life extending of Iranian salmon fish fillet was studied based on edible coating of whey protein concentrate containing different concentrations of aqueous extract of dried saffron petals. In the first stage, the extraction process of aqueous extract of saffron petals was optimized by using of response surface model and by applying the variables of extraction time (15, 30 & 45 days) and ultrasound power (50, 100 & 150 W). Then, in the second stage, aqueous extract of saffron petals was extracted under optimal conditions and added to edible coating of whey protein concentrate at various levels and resulted coating was used to coating of salmon fillets. Following, the physicochemical (pH, peroxide value, Thiobarbituric acid, total volatile basic nitrogen, & color components), microbial (enumeration of mesophilic & psychrophilic bacteria, & mold) and sensory (general apparent, color, texture elasticity, aroma & overall palatability) quality indices of salmon were monitored at +4oC during the storage time (16 days). The result indicated that, with increasing the storage time to 16 days, the chemical quality indices of pH, peroxide number, thiobarbituric acid and volatile nitrogen bases of the whole salmon fillet increased. The results also showed that, the adding of aqueous extract of saffron petals to the edible coating reduced all chemical and microbial quality indices. In optimal conditions (i.e. the storage time of 6 days and the amount of adding of saffron petal extract to 3811 mg/L), the response values of peroxide number, thiobarbituric acid, total volatile basic nitrogen, mesophilic bacteria and psychrophilic bacteria were 1.08948 meq O2/[kg of oil], 0.71 mg MDA/[kg of fish], .11.1068 mg N2/[100 g of fish], 4.55 log10 CFU/g and 4.571 log10 CFU/g, respectively. Keywords: Fish fillet, Saffron Petals (Crocus sativus), Edible coating, Ultrasound extraction, Microbial & physicochemical properties, sensory evaluation.

Keywords: Keywords: Fish fillet, Saffron Petals (Crocus sativus), Edible coating, Ultrasound extraction, Micro