Effect of Cold Plasma on the Microbial Safety and Physicochemical Properties of Functional Supplement Powder

Cold plasma (CP) was used as an innovative nonthermal approach for the decontamination of a functional supplement powder containing fish oil, hydrolyzed fish protein, and shrimp lipid extract in a liposomal structure-a lipid-rich food matrix with high sensitivity to marine bioactive compound degradation. The supplement powder underwent CP treatment (air atmospheric) for 10-20 min at 8-12 kV, and its safety and physicochemical properties were investigated. Optimal conditions (20 min, 12 kV) resulted in a significant reduction in psychrotrophic bacteria, mesophilic bacteria, and mold and yeast by 2.88, 2.67, and 0.35 log CFU/g, respectively (p < 0.05). CP treatment not only enhanced the microbiological safety of the supplements but also preserved their sensory attributes such as taste, aroma, and flavor. However, CP treatment was associated with minor alterations in color parameters, antioxidant capacity, and lipid oxidation, as evidenced by an increase in peroxide levels (0.52-0.58 meqO₂/kg fat) and thiobarbituric acid values (1.36-1.65 μM) compared to the control samples (p < 0.05). These controlled oxidative changes highlight the potential of cold plasma for extending the shelf life of functional supplements containing heat-sensitive marine bioactive compounds while maintaining their nutritional and therapeutic value, addressing a key challenge in the functional foods industry.