BACKGROUND The effect of nanoemulsions prepared with grape seed and cinnamon essential oils on the shelf‐life of flathead mullet (Mugil cephalus) fillets was evaluated by determining physicochemical (pH, free fatty acids, peroxide value, total volatile base nitrogen (TVB‐N), and thiobarbituric acid reactive substances (TBARs)), sensory and microbiological (mesophilic aerobic bacteria, total psychrophilic bacteria, and Enterobacteriaceae counts) properties during 14 day storage at 2 °C. RESULTS The nanoemulsions showed good stability and low average droplet size. The results indicated that nanoemulsion treatments significantly prolonged the shelf‐life of the fillets. Treatment inhibited increases in pH and TVB‐N, and retarded lipid oxidation and hydrolysis. Sensory assessment revealed that treatment induced shelf‐life extension from 10 to 14 days, compared with controls. Microbiological analyses showed nanoemulsion treatment caused shelf‐life extension from 10 to 12 days with reduction of microbiological contamination by up to 1 log cfu g−1 in mesophilic and 1.5 log cfu g−1 in psychrotrophic bacteria. CONCLUSION Considering the results, grape seed and cinnamon essential oil nanoemulsions could be considered as novel antimicrobial and antioxidant materials for shelf‐life extension of flathead mullet fillets during cold storage. © 2021 Society of Chemical Industry.

Summary The impacts of natural preservatives such as olive leaf (Olea europaea L.) and sweet marjoram (Origanum majorana L.) extracts (OLE and SME) and cold storage on the fatty acid profiles of vacuum‐packaged tuna‐like muscles were evaluated. At the end of the storage time, the lowest content of the total saturated fatty acids (SFA) was observed in both ordinary and dark muscles of the treated samples (OLE and SME) whereas the highest content was found in their counterparts from the untreated samples (control). The total polyunsaturated fatty acid (PUFA) and total monounsaturated fatty acid (MUFA) contents decreased markedly in both ordinary and dark muscles of the control samples. In contrast, treated samples remained relatively stable throughout the storage time since the employment of plant extracts had protective effects against lipid oxidation and help maintain MUFA and PUFA levels in frigate tuna muscles. In addition, the PUFA/SFA ratio and polyene index which are considered important dietetic parameters showed that the used plant extracts (OLE and SME) did not result in a reduction in the PUFA/SFA ratio and prevented PUFA damage in both frigate tuna muscles during storage. Thus, the use of plant extracts such as OLE and SME can be recommended as natural preservatives for the fish processing industry.