Efficacy of cold plasma in producing Salmonella-free duck eggs: effects on physical characteristics, lipid oxidation, and fatty acid profile

Concerns related to foodborne pathogens necessitate the decontamination of avian eggs. Conventional decontamination methods, such as egg washing, usually use health-threatening chemicals (e.g. chlorine). Hence, innovative chemical-free decontamination approaches are interesting for the food industry, especially to decontaminate commonly Salmonella infected products such as duck eggs. The present study is the first attempt to evaluate the effectiveness of cold plasma against Salmonella enterica inoculated on the surface of duck eggshell. In this regard, Salmonella-contaminated duck eggs were treated by arc plasma for 10, 20, 30, and 40 s. The bacteria count, eggshell strength, color, pH, Haugh unit, acid value (AV), thiobarbituric acid reactive substances (TBARS), and fatty acid profile of the plasma-treated samples were then compared with those of untreated sample. According to the results, all the plasma treatments significantly decreased the Salmonella population and longer treatment times enhanced the bactericidal effects of plasma. A maximum bacterial reduction of 4.1 log cycle was observed when plasma was applied for 40 s. Furthermore, plasma treatments did not deteriorate the quality parameters of eggs such as eggshell strength, eggshell color, yolk color, Haugh unit, AV, and TBARS. These findings introduced arc plasma as an emerging tool for improving the safety of duck eggs with good potential for industrial application.