In this study, the effects of the different concentrations of rosemary (Rosmarinus officinalis) extract on the shelf life of hot-smoked and vacuum-packed Luciobarbus esocinus fillets were investigated in terms of its microbiological, chemical and sensory quality. The results showed that rosemary extract had a significant effect on lactic acid bacteria, psychrophile bacteria, yeast-mold, thiobarbituric acid and peroxide value during storage (P < 0.05). The shelf lives of smoked L. esocinus fillets to which rosemary extract was added were determined to be 42 days for 400 mL/L, 84 days for 600 mL/L and 800 mL/L brine. Also, that in the control group (without rosemary extract) was determined to be 42 days. Rosemary extract was effective in controlling the growth of bacteria and chemical indices. PRACTICAL APPLICATIONS Hot smoked fish stored in anaerobic conditions is very sensitive to deterioration and, based on sensory evaluation, has a limited shelf life ranging from 3 to 4 weeks at refrigerator temperature. Natural extracts have proven to be an effective preservation method for the extension of shelf life of foods. Our study has clearly shown that addition of rosemary extract in smoked fish resulted in longer shelf life, and this method could be commercially used.

It is important that the methods and materials used for to lengthen the shelf-life of food are simple, inexpensive and safe. For these reasons, herbal additives like cumin oil (Nigella sativa L.) have been preferred recently. Thus, the present study focuses on the influence of black cumin oil on chemical, microbiological and sensory quality of fish (Barbus grypus) fillets during storage at 2 ± 1 °C. Acceptability scores for sensory quality of all described treatment groups decreased with storage time. Defined limits for mesophilic bacteria and Total volatile basic nitrogen (TVB-N) were reached after 21^st days for the control group, after 24^th days for with 0.2% black cumin oil treated group and after 28^th days for with 0.4% and 0.6% black cumin oil treated groups. No difference was found among groups during storage in terms of defined thiobarbituric acid (TBA) values. Consequently, it was found that black cumin oil treated groups had longer shelf-life and higher sensory quality than the untreated control group.