The safety of sea bass is critical for the global food trade. This study evaluated the effectiveness of atmospheric cold plasma in reducing food safety risks posed by Salmonella Enteritidis and Listeria monocytogenes, which can contaminate sea bass post harvest. Cold plasma was applied to inoculated sea bass for 2 to 18 min, achieving a maximum reduction of 1.43 log CFU/g for S. Enteritidis and 0.80 log CFU/g for L. monocytogenes at 18 min. Longer treatments resulted in greater reductions; however, odor and taste quality declined to a below average quality in samples treated for 12 min or longer. Plasma treatment did not significantly alter the color, texture, or water activity (aw) of the fish. Higher levels of thiobarbituric acid reactive substances (TBARSs) were observed with increased exposure times. Cold plasma was also tested in vitro on S. Enteritidis and L. monocytogenes on agar surfaces. A 4 min treatment eliminated the initial loads of S. Enteritidis (2.71 log CFU) and L. monocytogenes (2.98 log CFU). The findings highlight the potential of cold plasma in enhancing the safety of naturally contaminated fish. Cold plasma represents a promising technology for improving food safety in the global fish trade and continues to be a significant area of research in food science.

Summary: Salmonella contamination of fish after harvest is a significant food safety risk. To control this risk, it was aimed to reduce Salmonella Enteritidis in sea bass by helium and air plasma. Considering that preserving the fresh properties of sea bass is important for industrial applicability, determining the sensory effects of plasma treatments was also aimed. Since air plasma would provide a cheaper and easier alternative to helium plasma, their effects were compared. Additionally, the in vitro effects of these treatments on Salmonella Enteritidis were also investigated. Air and helium plasma completely inhibited the initial load of S. Enteritidis (2.79 Log CFU) inoculated on agar surface after 10 min treatment. Then, the inoculated sea bass samples were exposed to air or helium plasma for durations ranging from 1 to 15 min. Air and helium plasma treatments for 10 min provided 0.90 log cfu g⁻¹ and 1.13 Log CFU/g reductions, respectively, but longer treatments did not lead to further significant reductions. Sensory scores were all above 7 (good) when samples were treated with air or helium plasma for 1–10 min, but longer treatments resulted in lower scores. The reduction of S. Enteritidis and changes in sensory characteristics were interpreted together and it was concluded that 10 min of air or helium plasma provided maximum reduction without causing any significant sensory changes. Overall, the current study showed that atmospheric pressure air and helium plasmas can be useful for ensuring post‐harvest safety in the fish trade.

Whole chilled sea bass is an essential product for the European food market, and Türkiye is the foremost supplier. The importance of sea bass in the world food trade reveals the significance of food safety risks that may arise during or after harvest. This study aimed to examine the impact of atmospheric cold plasma (ACP) on delaying the spoilage of sea bass. The ACP is generated by an original device that produces a dielectric barrier discharge plasma using an alternating current (AC) power supply, applying a 30 kV high voltage with a sinusoidal frequency of 20 kHz. Whole sea bass samples were treated for 1 min (ACP1) or 7 min (ACP7), and then stored at 2 ± 1 °C. Sensory scores of plasma-treated sea bass were higher throughout the storage period. Both treatments decreased the initial bacterial load and delayed bacterial growth (p ≤ 0.05) during storage. The mesophilic aerobic bacteria count of control samples exceeded 6 log CFU/g on the second day of storage. However, ACP1 and ACP7 did not reach this value until the third and fourth days. The control samples had higher TMA-N and TBARS (p ≤ 0.05) than plasma-treated groups. The treatment did not significantly change the texture. Although ΔE was higher in ACP samples, a discoloration that could affect acceptability was not reported during the sensory test. Cold plasma can improve the overall market value by maintaining quality, benefiting the global fish trade. It has been shown that cold plasma has promising potential in the fresh fish industry.