## 4 Discussion
In the studies by the same team, ultrasound treatment led to greater color changes, as it had a LWE brightening of over 11 L* units, as well as a statistically significant increase in yellow saturation and a decrease in red saturation [33]. In our own research, after the CMF treatment, there was a slight darkening of the LWE samples by about 3 L* units and a slight decrease in the saturation with yellow color by about 2 units, with similar values of the a* parameter of red color. Similar relationships were found in the case of the yolk. The color differences after CMF treatment were smaller in egg white. It was also found that the color of egg products after CMF treatment is significantly negatively correlated with active acidity, although for different raw materials and color components, i.e., for egg white pH and parameter a* (R = \(-\)0.670), for yolk pH and L* parameter (R = \(-\)0.669) and for the pH of the LWE the parameter L* (R = \(-\)0,858) and the parameter b* (R = \(-\)0.807). These correlations indicate specific color components that are most susceptible to change in different egg raw materials after CMF treatment. The main reason for this may be the different chemical composition and the way of complexing individual chemical compounds within the egg white, yolk and liquid whole eggs. Liquid egg products are typical non-Newtonian fluids. Their apparent viscosity depends on shear rates, which is connected with shear-thinning characteristics [36]. The greatest changes in the value of apparent viscosity (from approximately 104 mPa-s to approximately 120-130 mPa-s) were observed in the case of the yolk subjected to the high-energy CMF treatment (at the level above 3.5 kJ) and at the same time shorter intervals between pulses (0.5-0.8 s). The smallest effect of CMF on apparent viscosity was found for liquid whole eggs. LWE and yolk are composed of proteins, phospholipids and triacylglycerlecrools, whose interactions are easily destroyed by a high shear force [37]. Nevertheless the shape of the apparent viscosity curves of all egg raw materials are similar at a high shear rate. It is well known that the shear molecules are oriented in one direction, so the resistance to fluid is reduced [38]. CMF treatment significantly influenced the thinning of the egg white while the yolk had thickened and there was no significant effect of CMF on the apparent viscosity of LWE. It follows that CMF interactions did not break down the protein\(-\)lipid complexes in the yolk, therefore, along with the increase in the intensity of the process and the higher final temperature of the yolk, its apparent viscosity increased due to denaturing processes. In order to reduce the apparent viscosity of the yolk, an additional preservation process should be used in the \"hurdle technology\", e.g., high pressure carbon dioxide (HPCD), the effectiveness of which in lowering the viscosity of LWE was proven by [PERSON] et al. [39]. On the other hand, our research shows the possible effectiveness of CMF in thinning the egg white. The apparent viscosity was not correlated with other analyzed factors. It is worth mentioning that the mechanism of microbial inactivation in food during exposure to the microwave field is not entirely clear. There are several theories on this subject. One of them, called the theory of selective heating, assumes that microorganisms are heated more selectively by the microwave field compared to the surrounding environment, which leads to their inactivation. According to the theory of electroporation, the potential difference on both sides of the bacterial cell membrane causes damage and the formation of the so-called \"pores\" through which cellular content passes out, which leads to the death of the bacterial cell [16]. In turn, a similar theory of rupture of the cell membrane assumes that the destruction of the cell membrane through ruptures occurs as a result of the generated electrical voltage.