Investigation of the effect of gelatin and chitosan based active edible coating on quality of pearl mullet

In this study, effect of gelatin and chitosan based active edible coating on quality of pearl mullet was investigated. 4 different coatings formulated with chitosan, rosemary extract and rosemary oil as active ingredients were used for coating of pearl mullet fillets and coated samples were cold stored at +4°C for 15 days. During storage, some chemical, physical and microbiological quality parameters were periodically analyzed. In addition, fatty acid profile of pearl mullet and antioxidant activity of coatings were determined. According to the results obtained, it was determined that PV was limited in samples coated with rosemary extract and rosemary oil formulated coatings. On the other hand, there were significant changes in the content of FFA, CDens and CTens, but not primarly because of coatings. In the first days of storage, limiting effects of coatings with active ingredients were obvious on formation of TMA and TVB-N, but later on, this effect was dimished and disappeared. Beginning pH value of pearl mullet fillets were determined to be 6.80 and significant changes were observed during storage, but again, not primarily because of coatings. Visible differences were observed in color of coated samples and these differences were sustained during the whole storage. Regarding the microbiological quality, counts of TMAB and PB were followed and lower counts were observed especially for the first half of the storage in coated samples in comparsion with the control. This study revealed the positive effect of coatings formulated with chitosan, rosemary extract and rosemary oil on fish quality beside with necessity of further studies to investigate which active ingredients should be used with which carrier polymers at what concentrations.