## 3 Results and Discussion
### Physicochemical and Microbiological Properties
#### 3.2.2 Microbiological Characteristics of Meat  
The research showed that the combined application of the used techniques led to a significant (\(p<0.05\)) reduction in the overall microorganism count during the cold storage period in comparison with the control sample. Furthermore, two-way analysis of variance indicated that both the treatment applied and the storage duration had a statistically significant impact on the total microbial load. sMicrobial inactivation is a non-selective process primarily driven by photochemical effects. The extent of reduction is influenced by factors such as the type of meat, its chemical composition, and the specific characteristics and physiological state of the microorganisms present [44; 45]. According to the literature [44; 45; 46], the pulsating light stream damages cell membranes, leading to a reduction in the overall number of microorganisms. The combination of the used techniques reduces the microorganism count in meat stored under refrigeration, primarily by impairing their ability to grow, proliferate, and endure harsh conditions. The synergistic effect of these two factors can disrupt microbial cellular structures, induce oxidative stress, and enhance the effectiveness of photodynamic action. Consequently, this treatment allows the meat to retain higher quality and an extended shelf life during storage. Similar findings were reported by [PERSON] et al. [39], who investigated the effect of pulsating light on the quality and shelf life of the _longissimus dorsi_ muscle of pigs stored under refrigerated conditions. The authors demonstrated that the treatment caused a decrease in the total number of microorganisms compared to the control group throughout all refrigerated storage periods. [PERSON] et al. [47] reported a reduction in the populations of _Escherichia coli_, _Leclercia aderboxylata_, and _Staphylococcus aureus_ following exposure to a moderate magnetic field (10 mT) at 50 Hz for up to 30 min. In a similar study, [PERSON] et al. [48]demonstrated that exposure to the same magnetic field parameters (10 mT, 50 Hz) for up to 24 min resulted in a decrease in the population of _Saccharomyces cerevisiae_ and inhibited their growth. The authors suggested that bacteria exhibit a higher sensitivity to magnetic field exposure than yeasts, which is likely attributed to the structural differences between eukaryotic and prokaryotic cells. Furthermore, [PERSON] and [PERSON] [49] demonstrated that a rotating magnetic field serves as a trigger for Gram-positive bacteria, including _Staphylococcus aureus_ ATCC 43300, _Enterococcus faecalis_ ATCC 29212, and Streptococcus mutans ATCC 35668. This treatment, administered at a constant intensity (18 mT for 8 h), effectively inhibited the growth of Gram-negative bacteria, including _Escherichia coli_ ATCC 8739, _Serratia marcescens_ ATCC 274, and _Klebsiella oxytocin_ PCM 22. Similarly, other authors [50] observed a reduction of approximately 1 log in specific pathogens in tuna and beef carpackio treated with pulsed light, despite applying significantly higher fluences of up to 8.4 and 11.9 J/cm\({}^{2}\). [PERSON] et al. [51] explored the effects of pulsed magnetic field treatment on meat samples, particularly the Supraspinatus muscle from Angus cattle. Unlike most studies, which generally focus on short-term PMF exposure, this study involved longer treatment durations, specifically 2 h and 12 days, under dark conditions. Notably, meat samples exposed to PMF (1 Hz) for 2 h showed no significant change in total aerobic plate count after 12 days of refrigeration. After 12 days, the aerobic plate count of the control sample increased by 2.0 log10 cycles. In comparison, the PMF-treated samples showed increases of only 0.7 and 1.5 log10 cycles for the 2 h and 12-day exposures, respectively.