The objective of this study was to modify polyethylene (PE) film for better antibacterial capacity via phase transition. Lysozyme solution at 2 mg/mL was mixed with an equal volume of tris(2-carboxyethyl)phosphine (TCEP) solution at 10 mmol/L. The modification efficiency of PE film by amyloid-like aggregates produced from phase transition in the lysozyme solution was evaluated at different reaction times. The results indicated that the average size of phase-transited lysozyme particles increased from 531.2 to 2305 nm with increasing reaction time up to 60 min. According to the results of Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), the surface of modified PE film was grafted with hydrophilic groups such as carboxyl, hydroxyl and amino groups. In addition, the oxygen content increased, and the elements S and P were found in the surface coating but not in the native film. The coating formed at 120 min was homogenous and compact without excessive fusion, and it stably adhered to the PE film under different temperature conditions. The modified PE film showed better antibacterial effect against Staphylococcus aureus than the uncoated one, thus providing a better packaging environment for foods.

This study investigated the effects of different ozone treatment times (0, 10, 20, 30, 40, and 50 min) on off-flavor removal from egg white powder (EWP) and the underlying mechanism. Results showed that compared with the untreated group (0 min), ozone treatment reduced the contents of the characteristic off-flavor substances (geranyl acetone, 1-octen-3-ol, octanal, and nonanal) in EWP by more than 40.94%. The sensory off-flavor score reached its lowest point (which decreased by 75% compared with the untreated group) after 20 min of ozone treatment, when egg white protein was slightly oxidized, leading to protein unfolding and structural disordering, increased carbonyl content and particle size, and decreased endogenous fluorescence intensity. In addition, fluorescence quenching and molecular docking showed that the major binding force between egg white protein and off-flavor substances was hydrophobic interaction, and their main binding sites were in a hydrophobic cavity composed of amino acids such as Leu66, Lys69, Glu87E, Ala87F, Cys87H, Glu129, Tyr130, Cys133, and Gly320. Ozone treatment for 20 min reduced the hydrophobic interaction between egg white protein and off-flavor substances by 45.98% compared with the untreated group, releasing off-flavor substances and reducing sensory off-flavor score, thereby ultimately deodorizing EWP. In conclusion, ozone treatment can reduce the off-flavor of EWP, the most pronounced effect being observed after 20 min treatment.

Lysozyme, as one of the major proteins in egg white, has been widely used in the food, medicine and aquaculture fields due to its rich content and excellent antibacterial activity. Despite its notable efficacy against Gram-positive bacteria, lysozyme exhibits a lower sensitivity to Gram-negative bacteria, hindering its broader industrial application. In addition, the antibacterial activity of egg white lysozyme is affected by complex application environments and its duration of action. To bolster its antibacterial power, lysozyme is modified through various methods, including physical, chemical and biological modifications. This article presents a comprehensive review of the recent literature on the antibacterial properties of egg white lysozyme from four aspects: extraction and purification, antibacterial mechanism, modification techniques and application. It aims to shed new light on the molecular mechanism behind lysozyme’s antibacterial action in order to maximize the application value of egg white lysozyme and to provide a theoretical foundation for expanding its application in various industries.

Egg yolk is an important food ingredient because of its outstanding nutritional value and emulsifying properties. The insoluble particle structure present in egg yolk and heat treatment during food processing may lead to poor stability of egg yolk emulsion. Hydrolysis, as a safe, efficient and low-energy modification method, has been widely used in studies on improving the emulsifying properties of egg yolk. In this paper, the effects of hydrolysis on the molecular structure, physicochemical properties and emulsifying characteristics of egg yolk are reviewed. Taking into account the actual needs of production, the formation mechanism and removal process of off-flavor in egg yolk hydrolysis products are discussed. Finally, this review summarizes the application of the emulsifying properties of egg yolk in the field of food processing, with a view to providing theoretical references for research on the hydrolytic modification of egg yolk.