To regulate lipid oxidation caused by plasma treatment in meat, this study investigated the effect of treatment with essential oil blend in combination with cold plasma (CP) on the preservation and lipid oxidation of salted duck. Oregano oil, cinnamon oil, and rosemary were used to prepare the essential oil blend. Meanwhile, the effect of CP treatment on the antibacterial properties, total phenolic content, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity of the essential oil blend was investigated. In addition, the total bacterial count, E. coli count, color, and lipid oxidation of salted duck after treatment were measured during an 18-day storage period. Results showed that the total phenolic content and DPPH radical scavenging capacity of the essential oil blend were not affected significantly by CP treatment. But the essential oil at a concentration ranging from 0.100% to 0.125% combined with CP reduced the E. coli count by 8(lg(CFU/mL)). Moreover, the combined treatment could significantly increase the storage life of salted duck with no significant effect on meat color, and reduce the thiobarbituric acid reactive substance value from 6.87 mg/kg to 4.58 mg/kg compared to the CP treated group.

The spoilage and quality deterioration of packaged low-salt paocai products caused by microorganisms has become a technical bottleneck restricting the development of the paocai industry. In order to overcome this problem, this experiment explore the effect of dielectric barrier discharge (DBD) cold plasma treatment on the inhibition of pellicle spoilage and the storage quality of instant low-salt paocai. With this in mind, the microbial population, physicochemical properties, color difference, texture and volatile compounds of paocai samples were investigated. Results showed that DBD cold plasma treatment reduced the total viable count and yeast count by 1.54–3.55 and 2.12–4.21 (lg (CFU/g)), respectively, and completely killed coliform bacteria while allowing the retention of lactic acid bacteria. Moreover, it inhibited the growth of pellicle-forming yeast obviously, thereby effectively controlling the pellicle spoilage of paocai during storage. In terms of physical and chemical properties, DBD cold plasma could inhibit the increase of pH and increase significantly the brittleness, brightness, yellowness and total acid content compared with pasteurized paocai (P < 0.05). Although higher than that in pasteurized paocai, the nitrite content in DBD cold plasma treated paocai was still far lower than the national standard limit, and gradually decreased to 3.13 mg/L as fermentation proceeded. Additionally, the major volatile compounds of paocai changed little within a short time after DBD cold plasma treatment, and DBD cold plasma treatment could inhibit the odor caused by the increase in the content of dimethyl sulfides during storage. Therefore, DBD treatment could effectively control the pellicle spoilage of low-salt paocai during storage while ensuring its quality characteristics.

In this study, the effect of treatment with plasma-activated water (PAW) on the biogenic amine content and sensory quality of air-dried pork tenderloin was investigated with the aim of exploring the feasibility of applying cold plasma technology in dried meat products. PAW was prepared using a dielectric barrier discharge (DBD) system at voltages of 50, 60 and 70 kV. Dried meat products were prepared by curing pork tenderloin with NaCl dissolved in PAW or pure water, followed by drying and maturation. The pH, nitrite residue and biogenic amine content of the products were analyzed. The flavor composition was studied using an electronic nose combined with principal component analysis (PCA) and loading analysis (LA). Finally, sensory evaluation was carried out. The results showed that (1) the amount of residual nitrite in the 50, 60 and 70 kV treatment groups were 8.12, 10.11 and 15.24 mg/kg, respectively, which were all lower than the national maximum allowable limit; (2) PAW treatment significantly inhibited the formation of biogenic amines in products, at 50, 60 and 70 kV voltages decreasing cadaverine content by 8.21%, 11.29% and 19.49% and spermine content by 9.64%, 16.54% and 27.56%, respectively (P < 0.05); (3) electronic nose analysis showed that the overall flavor difference between the PAW and control groups was not significant; and (4) sensory evaluation results showed that there was no significant difference in the flavor, taste, texture or acceptability between the PAW and control groups, while high-intensity PAW treatment could impart a better color to products.

Postharvest microbial contamination of strawberries has become a topical issue for safety and quality control in the logistics process. In this study, the effect of combined cold plasma-activated water (PAW) and dielectric barrier discharge (DBD) treatment on the sterilization and quality of strawberries was explored. One-factor-at-a-time experiments were carried out to investigate the effect of PAW preparation time, salicylic acid concentration, and soaking time as well as DBD working voltage, time and frequency on the total bacterial count (TBC) on the surface of strawberries. The significant variables affecting the response variable were determined using Plackett-Burman (PB) design and were optimized using Box-Behnken design. Results showed that the TBC on the surface of strawberries decreased first and then leveled off with increasing PAW preparation time and salicylic acid concentration, while it continuously decreased with increasing DBD working voltage and time. Nevertheless, when DBD working voltage and time exceeded 60 kV and 150 s, respectively, the appearance of fruit color was faded and even damaged. Soaking time and working frequency had no significant effect on the TBC (P > 0.05). Besides, salicylic acid concentration, PAW preparation time and DBD working voltage were the significant variables affecting the TBC (P < 0.001), ranked in decreasing order of importance. The critical values of salicylic acid concentration and DBD working voltage both showed a linear downward trend with PAW preparation time. The optimum values of PAW preparation time, salicylic acid concentration and DBD working voltage were found to be 96 s, 1.1 mmol/L and 46 kV, respectively. Under these conditions, the TBC decreased from 3.64 (lg (CFU/g)) to 0.83 (lg (CFU/g)) and the sterilization rate was 99.8%. The combined treatment could obviously inhibit the growth of microorganisms at 20 ℃ for 8 days, effectively maintain the quality and extend the shelf life of strawberries.