The effect of antioxidant and antimicrobial of Coriandrum sativum essential oil on shelf life of Otolithes ruber fillets at 4 ºC

This study has been carried out to investigate the antioxidant and antimicrobial effect of the coriander essential oil (Coriandrum sativum) on shelf life of Otolithes ruber fillets. In this study, the antioxidant property in different concentrations was compared with the synthetic antioxidant BHT using the 2.2.Diphenyl-1-picrylhydrazyl method. Moreover, the bio-chemical (pH, TVN, TBA, PV, FFA) and microbial parameters (PTC, PVC) have been studied using the control sample (treatment1), the fillet containing 1.5% essential oil (treatment 2) and the fillet containing 3% essential oil (treatment 3) for 15 days at 40C. The results showed that in assessing the antioxidant property, IC50 was determined 0.79 (mg/ml) for the coriander essential oil. The pH in Otolithes ruber fillet had an increasing trend from the first to fifteenth day. The volatile nitrogen bases rate had a significant difference (P< 0.05) in day 15. The level of thiobarbituric acid in treatment 2 had a significant difference (P<0.05) in days 12 and 15. The peroxide value was determined respectively as follow: in control treatment in day 12 (6.10±./13 Meq/ kg) and in treatments 1 and 2 on day 0 (0.98±./14 Meq/ kg). The level of free fatty acids between in treatments had a significant difference (p<0.05) on day 15. The total psychrophilic Bacteria and total bacteria count were higher than the standard of the total microbial load (7log cfu/g). The results showed that according to chemical and microbial analysis, the best time for shelf life of Otolithes ruber fillets under the effect of the coriander essential oil during 15 days of storage at the refrigerator temperature was achieved in 3% coriander essential oil treatment.