Cold plasma treatment enhances physicochemical, microbial, and sensory properties of raw sheep milk and Lighvan cheese

This study investigated the effects of cold plasma (CP) treatment on raw sheep milk and Lighvan cheese. Physicochemical, microbiological, and sensory attributes were evaluated. Proteolysis and lipolysis were assessed using soluble nitrogen (SN%), non-protein nitrogen (NPN), and free fatty acids (FFA). Structural and compositional changes were analyzed through scanning electron microscopy (SEM), gas chromatography (GC), and sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE). CP treatment led to an increase in SN% (from 6.09% to 7.09%) and FFA content (from 0.5853 to 2.38 meq KOH/100g fat), indicating enhanced enzymatic activity. GC analysis revealed elevated levels of beneficial fatty acids, including C16:0, C18:0, and C18:1. SEM observations showed increased porosity and notable structural changes, contributing to improved texture. Sensory evaluation demonstrated significant improvements in flavor, texture, and overall acceptability. CP treatment also enhanced textural parameters such as hardness, elasticity, and cohesiveness. Statistical analyses, including ANOVA and variance decomposition, confirmed the significant effects of voltage, treatment duration, and storage time. Overall, CP proved to be a safe, non-thermal technology that improves the quality of milk and cheese by enhancing their biochemical, structural, and sensory properties, supporting its potential application in traditional dairy processing.