Cold Plasma Controls Nitrite Hazards by Modulating Microbial Communities in Pickled Radish.

Area of Science:

• Food Science and Technology
• Microbiology
• Plasma Physics

Background:

• Nitrite accumulation poses a significant food safety risk in pickle production.
• Current methods for controlling nitrite often involve additives.
• Microbial community regulation offers a potential additive-free approach to manage nitrite hazards.

Purpose of the Study:

• To investigate the use of cold plasma for controlling nitrite hazards in pickles by modulating the microbial community.
• To assess the impact of dielectric barrier discharge (DBD) cold plasma on bacterial populations and nitrite levels during radish pickle fermentation.

Main Methods:

• Radish pickles were treated with dielectric barrier discharge (DBD) cold plasma (40 kV, 60 s).
• Microbial community analysis using colony counting, qPCR, and high-throughput sequencing.
• Monitoring of fermentation parameters including pH and nitrite concentration dynamics.

Main Results:

• DBD cold plasma preferentially sterilized Gram-negative bacteria, which can produce nitrite.
• Gram-positive bacteria, including beneficial lactic acid bacteria, were retained, enhancing acid production.
• The treatment led to accelerated nitrite self-degradation, significantly reducing peak nitrite levels and overall accumulation.

Conclusions:

• DBD cold plasma effectively regulates the microbial community structure in radish pickles.
• This regulation inhibits nitrite generation and promotes its degradation, offering an additive-free solution for nitrite hazard control.
• The findings provide a valuable reference for controlling nitrite in fermented foods.