## 1 Introduction
All plasma production processes for food applications, such as dielectric barrier discharge, high-voltage electrical discharge, or plasma jet, must generate plasma at low temperatures in order to maintain food quality, sensory and nutritional properties and microbial safety. Sterilisation, which includes thermal, chemical and radiation processes, is normally used to inactivate microbes. However, sterilisation by heat processes cannot be used on heat-sensitive materials as permanent and irreparable damage may occur. When sterilising with chemical processes and radiation, it is important to protect staff and their workplace. The most important application of non-thermal plasmas is the sterilisation of various surfaces, including sensitive ones, as they can deactivate microorganisms without damaging them. Non-thermal plasma technology is suitable for both solid and liquid foods. Due to the high diffusivity of the plasma's active chemical components, this treatment works quickly and on the entire food surface. Non-thermal plasma technology is environmentally friendly [23] and energy efficient as it requires low energy input [24; 25]. The fact that non-thermal plasma consists of positively and negatively charged particles, ions and electrons, quanta of electromagnetic radiation, and excited and unexcited atoms and molecules makes it an effective means of decontamination [26]. To achieve the desired results, the appropriate plasma source must be selected and the plasma parameters (applied voltage, direct or indirect irradiation, type of gas, treatment time, etc.) must be adjusted [27]. Optimisation of decontamination is necessary to achieve successful elimination of the target microbial population. Analysing the effects of plasma on cellular targets also allows for a better understanding of the antimicrobial effect of non-thermal plasma [28; 29; 30; 31; 32]. Non-thermal plasma treatment technology for food preservation has a recognised potential to simultaneously meet consumer demands and deliver high-quality processed foods with extended shelf life, without additives and without heat treatment [33; 34; 35]. Due to the conditions under which non-thermal plasma processes are carried out, the results are very satisfactory for consumers, as the degradation of nutrients is minimised and high quality and greater freshness are perceived [36]. Non-thermal plasma technology also has practical applications in food packaging. The influence of cold plasma on the polymer materials used for this purpose is particularly important. Non-thermal plasma surface treatment of packaging material can be used as a surface pre-treatment for cleaning or activation, surface deposition, surface functionalisation, surface etching or surface sterilisation. The advantage of non-thermal plasma over the various chemical processes (using chemicals such as hydrogen peroxide, sodium benzoate, sorbic acid, phthalates, adipates, etc.) used in the food packaging industry is that it is a simple, safe and environmentally friendly alternative [37; 38]. High-voltage electrical discharge is a process in which current flows from a high-voltage electrode into a neutral fluid (gas, liquid) and ionises it completely or partially. A discharge channel is created in the area of the electrode, which is characterised by a highly conductive plasma due to the high temperature and density of the electrons in the plasma. The method of high-voltage electrical discharge based on the application of plasma is used in the food industry to extract bioactive components [39; 40; 41], to inactivate microorganisms [42; 43; 44], and to maintain food quality [45; 46; 47], as well as to replace conventional food processing methods such as pasteurisation and sterilisation. Despite the many proven benefits of using non-thermal plasma technology in the food sector, there are also some challenges and limitations that need to be considered. Plasma systems are complex systems where it is not easy to monitor the interaction of the reactive species with the food components.