The Effect of Atmospheric Plasma on Cold Thermal Stability of Powdered Whey Protein Isolate
Thermostability is the capacity of a material to withstand irreversible change in its structure by resisting extreme external factors such as high relative temperature. Extensive efforts toward making protein-based biological substances such as vaccines thermally stable have been made by implementing treatments such as lyophilisation, biomineralization, and encapsulation in sugar glass and organic polymers. These substances have a typically short shelf life, as they denature and degrade at room temperature over time. Furthermore, efficient storage and distribution relies on continuous refrigeration in order to preserve protein stability. However, this is costly and not always effective, as any disturbance in storage and distribution conditions may lead to rapid loss of effectiveness and potency. Whey protein isolate is used in a wide variety of food applications and is at risk of exposure to freezing temperatures during its transportation, which in turn could affect its stability as well as chemical and physical structure. This study examines the effects of plasma surface modification (PSM) on whey protein thermostability. Here we report on structural changes in commercially available whey protein exposed to cold thermal conditions, as reported by the Protein Thermal Shift Assay (PTSA). An improvement of 48% in protein thermal stability was observed upon treatment with PSM, suggesting that PSM may reduce damage caused by temperature fluctuations.