## 1 Introduction  
Colostrum is the first milk for newborn mammals. It is a valuable source of nutrients and contains numerous bioactive compounds crucial for mammal growth and development, such as immunoglobulins, lactoferrin, lactoperoxidase, lysozyme, lactalbumin, hormones, enzymes, and whey proteins [1]. Immunostimulatory: lactoferrin, colostrin, cytokines, and leukocytes are particularly important in colostrum as they modulate the newborn immune system [2, 3]. The composition of colostrum is highly variable in terms of protein, fat, cytokines, growth factors, carbohydrates, vitamins, and minerals content. It depends on many factors, such as the breed and age of the animal, prepartum nutrition, and the course of birth. The functional features of colostrum proteins are determined by the properties and structure of their molecules. Their size, shape, spatial arrangement, ability to create conglomerates, susceptibility to denaturation, and amino acid sequences are among the most important features. Colostrum contains more than 30 different proteins, which can be divided into two groups: casein (75-80%) and whey proteins (up to 20%) [4]. Nineteen amino acids have been determined in colostrum proteins, including all essential amino acids [5]. The most critical group of colostrum proteins are whey globular proteins. In bovine colostrum, there are \(\alpha\)-lactalbumin (15-20%) and \(\beta\)-lactoglobulin (55-65%) fractions, as well as immunoglobulins (9%), bovine serum albumin (BSA) (5.5%), lactoferrin, lactoperoxidase, phospholipidproteins, bioactive factors and enzymes [6]. In addition to their nutritional value, they also exhibit functional activities, including, most notably, immunomodulatory and antioxidant activity. They also regulate fatty acid synthesis in the liver, mitigating oxidative damage to DNA and oxidation of LDL [7]. Bovine colostrum has recently been used as a functional food, i.e., food of natural origin that benefits health. Unfortunately, most of the biologically active substances found in colostrum are thermolabile. Pasteurization degrades most desirable substances, including lactoferrin, depriving colostrum of its antigenic properties and ability to bind iron. In addition, spray drying of colostrum degrades lysozyme [8], and this technology does not guarantee the preservation of the health-promoting components of colostrum due to high temperatures. Therefore, freeze-drying is significantly more commonly used to stabilize colostrum. The abundance of nutrients and biologically active substances in colostrum, especially proteins with defensive properties for newborns and therapeutic and prophylactic properties for older animals and humans, has prompted the development of new non-thermal and highly energy-efficient techniques that can be used to effectively reduce microbial contaminants in food [9; 10; 11] while maintaining the stability of biological components. Cold plasma is a technology with a high potential for application in the food processing sector. Despite the fact it is essential from the quality and health and safety risk assessment perspective, there is a lack of information on the microbiological content of colostrum. According to [PERSON] et al. [12], the microorganisms isolated from colostrum can be divided into four groups: (1) pathogens from the mammary gland, which include: _S. uberis_, _S. dysgalactiae_ and _S.aureus_, (2) physiological flora of bovine skin and mucous membranes, e.g., _A. pyogenes_, _Corynebacterium_ spp., _Pasteurella_ spp., _Streptococcus_ spp., and yeast. (3) faecal contaminants, e.g., _Enterococcus_ spp., _E. coli_ and other coliform bacteria (_Klebsiella_ spp., _Enterobacter_ spp.) and (4) environmental contaminants, e.g., _Microoccus_ spp., _Bacillus_ spp., _Acinetobacter_ spp., _Pseudomonas_ spp., _Flavobacterium_ spp. Therefore, how colostrum is sourced and handled after milking should be performed in a way that reduces contamination and inhibits and eliminates further growth of microorganisms without lowering its biological properties.