Improving the Quality of Fresh Rainbow Trout by Sage Essential Oil and Packaging Treatments

The present study aimed to investigate the effect of addition of sage oil in different packaging conditions on the quality of fresh trout fillets during storage at 4C. Six different treatments were tested: A; (without sage oil, air packaged), A1; (added sage oil 2% v/wt, air packaged), A2; (added sage oil 4% v/wt, air packaged), VP; (without sage oil, vacuum packaged), VP1 (added sage oil 2% v/wt, vacuum packaged) and VP2 (added sage oil 4% v/wt, vacuum packaged). The results indicated that total mesophilic aerobe, psychrophile, yeast-mold and lipolytic bacteria reached higher populations in A, A1 and A2 groups (as compared to VP groups). In addition, significant differences were determined among groups in terms of total volatile basic nitrogen, Thiobarbituric acid, peroxide value and free fatty acid values (P<0.05) during the storage period. Based primarily on sensory evaluation, the use of VP, VP1 and VP2 extended the shelf life of fresh trout by ca. 14, 19 and 29 days, respectively. Practical ApplicationsEssential oils derived from spices and herbs have a wide application in food flavoring and preservation. Moreover, antimicrobial and antioxidant activities of essential oils are well-known. We hypothesized that vacuum packaged fresh trout with the addition of sage oil would increase shelf life. This work demonstrates that sage essential oil together with vacuum packaging treatments could be used to improving the quality of fresh rainbow trout.