Table 2.

Application of non-thermal atmospheric plasma (NTAP) technology to fish products; main results and limitations of the technology considered.

Fish Product	Treatment Conditions	Tested Microorganisms	Results	Limit	Reference
Dried filefish fillets (Stephanolepis cirrhifer)	Cold oxygen plasma (COP); treatment time, 3–20 min.	Cladosporium cladosporioides Penicillium citrinum	Reduction >1 log10 CFU/g was observed in the fillets treated with COP for >10 min.	Exposure to 20 min of treatment showed an increase in lipid peroxidation and a decrease in overall sensory acceptance.	[18]
Dried squid shreds	The corona discharge plasma jet (CDPJ) was generated using 220 V AC power with an output voltage of 20 kV DC, at a current of 1.50 A and a frequency of 58 kHz.	Total aerobic count Marine bacteria Staphylococcus aureus	Aerobic bacteria, marine bacteria and St. aureus were inactivated by 2.0, 1.6 and 0.9 log units, respectively. Additionally, a 0.9 log reduction in yeasts and mould contaminants was observed.	A change in moisture content and thiobarbituric acid concentration was observed. All other physico-chemical and sensory properties tested were unaffected.	[29]
Fresh mackerel fillets (Scomber scombrus)	Plasma was generated using voltages of 70 and 80 kV for different treatment times (1, 3 and 5 min).	Total aerobic count Psychrotrophic bacteria Pseudomonas spp. Lactic acid bacteria	There was no significant (p > 0.05) reduction in the total aerobic mesophilic count, whereas psychrotrophic bacteria, LAB and Pseudomonas counts were significantly (p < 0.05) reduced due to DBD.	Changes in immobilised and extra-myofibrillar water were observed. Mackerel was more susceptible to lipid oxidation. There was no negative influence on physico-chemical parameters such as pH and colour.	[42]
Chub mackerel (Scomber japonicus)	Plasma was generated using a voltage level of 0, 10, 20, 30, 40, 50, 60 and 70 kV and treatment times of 0, 15, 30, 45, 60 and 75 s.	Endogenous microbiota	Under optimal conditions at 60 kV for 60 s, the microbial count decreased substantially with a slowdown in bacterial proliferation and a reduction in the production of volatile bases and oxidation compounds. There was also a delay in myofibrillar protein degradation and an improvement in microstructure stability. The shelf-life was extended to 14 days against 6 days recovered for samples without this treatment.	Slight alteration of the chemical composition.	[43]
Smoked salmon	UV-C at 254 nm and a high-voltage plasma jet at 1 kHz were used, at predetermined time intervals (0, 1, 2 and 4 min), with intensities of up to 500 mJ/cm2.	Listeria monocytogenes Listeria innocua Salmonella Typhimurium Salmonella Enteritidis St. aureus Escherichia coli O157:H7 Aeromonas hydrophila Plesiomonas shigelloides	An additive lethal effect of the two techniques was found, with a reduction of 0.5–1.3 log CFU/g in the microbial population	High-energy treatments and long exposure times have caused significant changes in the appearance and oxidation of lipids	[44]
Asian sea bass slices	Plasma was generated using a voltage of 80 kV for 0, 2, 5, 7.5 and 10 min at room temperature (28 ± 2 °C).	Total viable count Psychrophilic bacteria H2S-producing bacteria Enterobacteriaceae Pseudomonas Clostridium perfringens Lactic acid bacteria	In treated samples, total viable count (TVC) was lower than the acceptable limit (log 106 CFU/g sample) within 18 days. The growth of various pathogenic and spoilage bacteria, including psychrophilic bacteria, Cl. perfringens (not detected), lactic acid bacteria (3.77–4.37 log CFU/g), Enterobacteriaceae (4.03–4.50 log CFU/g), Pseudomonas (6.62–6.82 log CFU/g) and hydrogen sulphide (H2S)-producing (4.04–5.05 log CFU/g) bacteria, of treated slices was lower than control samples. A 5-min treatment extended shelf-life to 12 days against 6 days recovered for samples without this treatment.	Pronounced lipid oxidation was observed in the 7.5 and 10 min treatments. There was also a reduction in the amount of PUFA and MUFA fatty acids by 28–64% and 40–46%, immediately after treatment and after 12 days of storage.	[23,24,33]
Refrigerated Asian Sea bass slices	Plasma was generated with an input voltage of 230 V at 50 Hz and an output voltage controlled within 0–120 kV.	Total viable count Psychrophilic bacteria Lactic acid bacteria Pseudomonas spp. H2S-producing bacteria Enterobacteriaceae Cl. perfringens	The shelf-life was extended to 15 days, while the control (kept in air) had shelf-life of 6 days.	Pronounced oxidation of proteins and lipids.	[26]
Asian sea bass slices (Lates calcarifer)	Cold atmospheric plasma was generated with a mixture of argon and oxygen (90% Ar/10% O2) for 5 min and used in combination with chito-oligosaccharides (COS) at different concentrations (0.05, 0.1 and 0.2 g/100 g).	Total Viable Count Psychrophilic bacteria Enterobacteriaceae Pseudomonas spp. H2S-producing bacteria Lactic acid bacteria Cl. perfringens	Reduction in L. monocytogenes, between 1.21 and 1.52 log CFU/g; reduction in S. Typhimurium, between 1.44 and 1.75 log CFU/g. The thiobarbituric acid reactive substances (TBARS) and peroxide values (PV) of treated samples were reduced. Sensory acceptability was improved.	No negative effects were found.	[34]
Grass carp (Ctenopharyngodon Idella)	Plasma was generated using air as the feed gas, at a current and frequency of 1.05 A and 10 kHz, respectively, under atmospheric pressure and an ambient temperature of 25 °C. The applied voltage was 70 V with a peak input power of 73.5 W.	L. monocytogenes S. Typhimurium	Logarithmic reductions were observed between 1.21 and 1.52 for L. monocytogenes and between 1.44 and 1.75 for S. Typhimurium.	Reduction in pH and increase in total acidity level in samples and change in colour.	[45]