## 1 Introduction  
The improvement and development of traditional food processes is mainly motivated by the improvement of food quality, as well as consumer demands for greater food variety. Novel food technologies are being developed to enhance food safety, prolong shelf life, and optimize the preservation of critical quality features, in response to these challenges. The application of cold plasma as a nonthermal technology has great potential, and is therefore currently of great interest to the food industry [1; 2; 3]. Cold plasma, a gas that is partially ionized by applying energy to it at atmospheric or subatmospheric pressures, contains a mixture of ions, electrons, free radicals, and ultraviolet photons [4]. The food industry has extensively adopted this technology for direct or indirect food treatment, primarily as a nonthermal processing method for food preservation and decontamination [3]. This is because the reactive species present in plasma, including ozone, hydrogen peroxide, other free radicals, and UV radiation, can impair the cell walls, membranes, and DNA of microorganisms, leading to their destruction [5]. In recent years, many studies have indicated that nitrite ions produced by plasma can provide comparable functionality to sodium nitrites [6; 7; 8; 9; 10; 11]. This is due to the fact that, during the discharge of a feed gas consisting of N\({}_{2}\) and O\({}_{2}\) molecules, collisions with electrons occur, leading to the formation of various nitrite oxides (such as NO\({}_{2}\), N\({}_{2}\)O\({}_{3}\), and N\({}_{2}\)O\({}_{5}\)). These oxides then react with water in food matrices, creating nitric and nitrate acids, which finally decompose primarily into nitrites [9; 12]. So far, the quality of conventional cured meat products (with sodium nitrite) has been compared with the quality of those subjected to direct nonthermal plasma treatment [11; 13; 14] or those containing ingredients produced using cold plasma, such as water [9; 15; 16; 17], winter mushrooms [10], onion [18], milk [19; 20], as well as soy and pea protein solutions [21]. The above studies have demonstrated promising results for alternative curing methods using nonthermal atmospheric plasma, taking into account both the physicochemical and microbiological properties of the finished products. Liver gates are traditional meat products that are still popular in many countries, mainly in Europe [22; 23]. Although they are characterized by numerous modifications of recipes (different types and proportions of raw materials, functional and seasoning additives) and technological process parameters that affect their quality and sensory characteristics, they are distinguished by the fact that their main ingredients are liver, fat, and meat [24]. Thanks to the use of appropriate technological processes, gates have good taste and a smooth texture [25]. Liver gates, in addition to proteins, could also contain minerals and vitamins such as calcium, copper, iron, zinc, magnesium, or vitamins B and A [26], making them both sensory acceptable and nutritious. The main advantage of this kind of product is the rich content of vitamin B\({}_{12}\), which, among other things, is involved in DNA synthesis, supports the nervous system, cardiovascular system, and energy metabolism [27]. The fact that they can be eaten both hot and cold has made liver gates a popular choice for consumers who are looking for convenient and ready-to-eat products [26]. Nevertheless, due to the high iron and fat content in the composition of liver gates, along with the high degree of processing involved in their production, they are extremely susceptible to lipid oxidation [28; 29] which could degrade their sensory quality by producing off-flavors, as well as changing their color and texture [30]. Taking this into account, producers usually add chemical preservatives to liver gates, not only to prevent bacterial growth, but also to extend shelf life by delaying oxidative processes of these high-fat products during storage.