## 1 Introduction  
### Application of Pulsed Electric Fields (PEF) in Food Processing and Pasteurization  
Thermal pasteurization of food products and beverages has specific drawbacks. During the process of thermal pasteurization, a fraction or the whole nutritional value of a product is lost because of the high temperatures applied to constituents such as vitamins and proteins found in raw food [1, 2, 3]. An inability to ensure daily intake of vitamins, proteins, carbohydrates, electrolytes, and fats leads to specific forms of malnutrition. Therefore, malnutrition can lead to other diseases, such as kwashiorkor, marasmus, or anemia [4]. The growing consumer demand for fresh, low-processed, and healthy foods has also prompted the food industry to look for alternatives to traditional pasteurization methods. Pulsed electric field (PEF) technology is an innovative method that has been adopted in the food industry. The first mention of juice and milk being pasteurized dates back to 1989-1990s, performed by the Krupp Industriotechnik GmbH company [5]. PEF processing technology has been widely adopted over the years and has been successfully used in fields such as medicine, food processing, and bio-based industries [6, 7, 8]. It has a wide range of applications in medicine for drug and gene delivery and in cancer research and laboratory settings for cell fusion [9, 10, 11]. In the food industry, such as juice and potato fry processing, it is shown to ensure higher juice yields and better quality of potato chips [12, 13, 14]. PEF is being applied in mild liquid food and beverage pasteurization [15, 16, 17].  
The applicability of PEFs has been discussed in several studies [17; 18; 19; 20; 21]. The main advantage of PEF technology in liquid food pasteurization is the ability to manage the amount of ohmic heating in food preservation (low-temperature processing), avoiding the Maillard reaction, which affects the functional properties of food, such as color, taste, and smell [22]. PEF is also effective in the inactivation of microorganisms such as _Salmonella typhimurium_, _Listeria innocua_, and _E. coli_ up to 5.0 log cycles [23]. The method is highly scalable and can be incorporated into existing food processing lines. In comparison to traditional heat pasteurization technology, it is more energy-efficient [6; 24]. Furthermore, PEF treatment chambers can be easily adapted to existing continuous-flow production lines for liquid food pasteurization [25]; however, achieving a homogeneous treatment may be an issue [26]. The main disadvantage of PEF technology is its effectiveness and efficiency, which are largely dependent on the liquid conductivity and viscosity [27]. Dielectric breakdown and non-uniform treatment may occur because of the existing air or gas bubbles [28]. It has been shown that electrode corrosion can be an issue during PEF as small amounts of electrode material may reside in the liquid being pasteurized [29; 30]. Another issue is bacterial spores, which are highly resistant to PEF technology, because of the spore outer coat and cortex; therefore, PEF can only be considered as a pasteurization technique and cannot be used for sterilization [31; 32; 33]. Nonetheless, liquid food sterilization by combining PEF and pressurized flow systems is gaining ground and is being tested in laboratory settings [34].