Effects of Ginger (Zingiber Officinale Roscoe) Essential Oil and Zein Pickering Nanoemulsion on the Shelf Life of Pufferfish (Takifugu Obscurus) During Cold Storage.

Seafood is susceptible to spoilage due to lipid oxidation, endogenous enzymes, and microbial growth. Pickering nanoemulsions (PN) containing active substances have emerged as a promising approach to enhancing preservation and extending shelf life. In this study, ginger (Zingiber officinale Roscoe) essential oil (GEO) and zein (Z) were homogenized by multi-frequency ultrasound to prepare a PN. The effects of PN with different concentrations (0, 0.1, 0.2, and 0.4%, v/v) of GEO on the preservation and bacteriostasis of puffer fish fillets were studied. The outcomes demonstrated that the TVC of the 0.4% GEO group samples was only 6.55 log CFU/g on the 18 day during cold storage, indicating that the GEO-Z-PN could effectively inhibit microbial growth. Thus, the pufferfish could maintain a low pH and slow down the changes in TVB-N and TBA. On the 18th day, the pH value was 6.25, the TBA value was 0.39 mg MDA/kg, and the TVB-N decreased from 42.32 to 21.01 mg N/100 g. Texture analysis also revealed that the 0.4% GEO group samples exhibited better muscle quality, characterized by higher hardness and chewiness. The results of water migration and tertiary structure showed that a 0.4% GEO treatment effectively alleviated the damage to the interprotein covalent cross-linking structure and the intermuscular fiber interaction force. Confocal laser scanning microscopy (CLSM) results showed that myofibrillar protein (MP) aggregation and inhomogeneity decreased in the 0.4% GEO group samples during cold storage. The shelf life of puffer fish might be increased from 9 days to 18 days with 0.4% GEO. PRACTICAL APPLICATION: This research holds practical value in the food industry. Through the utilization of the prepared PN containing ginger essential oil, the preservation of puffer fish fillets can be significantly enhanced. It is capable of prolonging the shelf life from nine days to 18 days, enabling consumers to enjoy fresher puffer fish products.