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Due to the side effects of artificial preservatives in meat products, the use of natural preservatives has increased. The aim of this study was investigated the effect of coating and nano-coating of chitosan (C)- Cress (Lepidium sativum) seed gum (CSG) on the shelf life of beef during 18-day at cold temperature. For this purpose, composite coatings including 33% C:6% CSG, 50% C:50% CSG, 66% C:33% CSG were prepared. The nano-coating was also constructed using ultrasound method. Antioxidant and antibacterial properties were measured and the results showed that the antioxidant and antimicrobial activity of the coatings incremented with increasing C content (66% C:33% CSG) and the antimicrobial and antioxidant activity of nano-coating was significantly higher than the coating (p < 0.05). In order to study the effect of coatings on the shelf life, four treatments including control, coating (66% C:33% CSG), nano coating (66% C:33% CSG) and sodium nitrite were prepared and chemical (peroxide value and total volatile nitrogen) and microbial parameters (total viable count, psychrotrophic count, Pseudomonas aeruginosa and Staphylococcus aureus) were studied at − 2, 4, and 8 °C for 18 days. Synthetic and natural preservatives delayed lipid oxidation and improved the chemical properties in beef. Also, microbial spoilage was significantly reduced compared to the control (p < 0.05). The nano-coating performed better than other treatments in all experiments (p < 0.05), and reduced the growth of pathogenic bacteria from the third day to the end of the period to below the permissible limit. Therefore, it seems that the nano 66% C:33% CSG can be used as a safe preservative in the active packaging of beef during refrigerator and freezer storages. [ABSTRACT FROM AUTHOR]

The effects of chitosan coating incorporated with eucalyptus essential oil and α-tocopherol on the quality of silver carp fillet during chilled storage (4 + 1°C) were examined over a period of 16 days. The control samples (without any coating), chitosan coating (CH), chitosan coating incorporated with eucalyptus essential oil (CH+EEO) and chitosan coating incorporated with eucalyptus essential oil and α-tocopherol (CH+EEO+α) were analyzed by chemical, microbiological and sensory characteristics. Results showed that, total viable counts, total psychrotrophic counts and total volatile basic nitrogen of CH+EEO and CH+EEO+α were significantly lower than control and CH ( P ≤ 0.05). Addition of α-tocopherol to EEO retarded lipid oxidation. According to the sensory analysis results, CH+EEO+α was acceptable even at the end of the 16-day storage. The results indicated that chitosan coating was improved extending of meat shelf life. Using eucalyptus essential oil and α-tocopherol increased its efficiency significantly. Practical Apllications Fresh fish are usually more perishable than most other muscle foods. Many attempts have been made to prevent the spoilage of fresh fish. To avoid the use of synthetic food additives, numerous studies are currently focused on using natural products to improve the quality of sea food products. The results of the present study report the efficacy of chitosan edible coating enriched with eucalyptus essential oil and α-tocopherol as a new natural preservative for developing the shelf life of silver carp fillets. [ABSTRACT FROM AUTHOR]