This study aimed to develop and characterize the chitosan-edible coating solution (CS-NH-TC) incorporated with ε-polylysine hydrochloride, tea polyphenols, Nisin, and ascorbic acid, then investigate their effect on physicochemical, antibacterial, and sensory properties of marinated eggs stored at 4 °C for 24 days, marinated eggs without coating were set as control. The CS-NH-TC edible coating solution exhibited the lowest particle size (582.6 ± 16.6 nm) and polydispersity index (0.49) and highest zeta potential (30.96) among the coatings. The FT-IR spectra showed that TP, VC, Nisin, and ε-PLH were successfully encapsulated in the CS edible coating solution. The moisture content and water holding capacity of the marinated eggs coated with CS-NH-TC remained stable up to 20 days. Marinated eggs coated with CS-NH-TC edible coating solution exhibited lower total viable counts of microorganisms, and more stable color and pH values compared to the control during the entire storage time. Furthermore, the texture and sensory evaluation results demonstrated that marinated eggs coated with CS-NH-TC edible coating solution had low degradation rate and improved overall acceptability scores. This study con rmed that CS-NH-TC edible coating solution is a promising coating for improving the quality and shelf life of marinated egg products and may have a broad application prospect in the preservation of other food products.

BACKGROUND Changes in storage temperature and time alter the functional properties of egg white powder (EWP) and determine its quality and shelf‐life, finally affecting the consumer acceptance of the products made from EWP. In the present study, the EWP samples were stored at four different temperatures (−20, 4, 25 and 37 °C) for 60 days, and then the protein structural, physical and functional properties of EWP were measured and assessed further for correlation with storage conditions using heatmap. RESULTS The viscosity of the EWP solution increased after 30 days. Foaming ability and rheological properties increased first and then decreased compared to untreated samples with the prolonged storage time. Correlation analysis results indicated that the gel hardness, water holding capacity, foaming ability, emulsifying ability, particle size, dispersibility and viscosity of EWP were significantly related to storage time (P < 0.05). Only the gelation properties of EWP stored at 37 °C for 60 days changed significantly and were negatively related to its moisture content (P < 0.05). Additionally, the random coil content of EWP was positively correlated with particle size, moisture content, solubility and gel properties, whereas β‐sheet was negatively correlated with them. CONCLUSION Compared to other temperatures, the functional properties of EWP were relatively stable under 4 °C. Therefore, the low temperature (4 °C) was selected as the most suitable storage temperature for EWP. The results of the present study could provide a theoretical basis for the shelf‐life extension of EWP. © 2022 Society of Chemical Industry.

This study aimed to develop and characterize the chitosan-edible coating solution (CS-NH-TC) incorporated with ε-polylysine hydrochloride, tea polyphenols, Nisin, and ascorbic acid, then investigate their effect on physicochemical, antibacterial, and sensory properties of marinated eggs stored at 4 °C for 24 days, marinated eggs without coating were set as control. The CS-NH-TC edible coating solution exhibited the lowest particle size (582.6 ± 16.6 nm) and polydispersity index (0.49) and highest zeta potential (30.96) among the coatings. The FT-IR spectra showed that TP, VC, Nisin, and ε-PLH were successfully encapsulated in the CS edible coating solution. The moisture content and water holding capacity of the marinated eggs coated with CS-NH-TC remained stable up to 20 days. Marinated eggs coated with CS-NH-TC edible coating solution exhibited lower total viable counts of microorganisms, and more stable color and pH values compared to the control during the entire storage time. Furthermore, the texture and sensory evaluation results demonstrated that marinated eggs coated with CS-NH-TC edible coating solution had low degradation rate and improved overall acceptability scores. This study confirmed that CS-NH-TC edible coating solution is a promising coating for improving the quality and shelf life of marinated egg products and may have a broad application prospect in the preservation of other food products.

Egg processing products lose their attractions due to protein oxidation, while the edible coating incorporating antioxidant and antimicrobial agents can address this deficit. In this work, chitosan (CS) in combination with ε-polylysine hydrochloride, tea polyphenols, nisin, and vitamin C (CS-NH-TC) was applied as a novel edible coating material for preserving marinated eggs for 20 days and its effects on protein oxidation and structure, including total sulfhydryl, dityrosine, protein solubility and hydrophobicity, intermolecular forces, particle size, turbidity, secondary structure, and microstructure were determined. Compared to uncoated marinated eggs (Sulfhydryl: 12.02 μmol/g, soluble protein: 1.13 mg/mL, dityrosine: 6251.8, protein hydrophobicity: 3691, turbidity: 0.13 mg/mL, particle size: 342.13 nm), CS- and CS-NH-TC-coated eggs exhibited improved protein stability, as evidenced by a higher sulfhydryl (22.20 and 30.92 μmol/g) and soluble protein content (1.31 and 1.42 mg/mL), and lower dityrosine content (4722 and 4216), protein hydrophobicity (2891.72 and 865.75), turbidity (0.06 and 0.03 mg/mL), and particle size (292.06 and 256.57 nm). Additionally, edible coatings, especially CS-NH-TC coatings, were positively correlated with smaller intermolecular force changes in marinated eggs, corresponding to suppressed oxidation and improved structural stability. Furthermore, CS-NH-TC-coated samples showed more stable protein secondary structures and less disorderly and aggregated protein microstructure. Our study could provide a theoretical basis for stabilizing the protein structure of egg processing products.