Effects of dielectric barrier discharge plasma on the physicochemical and functional properties of myofibrillar proteins
The present study was designed to investigate the effects of dielectric barrier discharge (DBD) plasma on myofibrillar proteins extracted from beef. For this purpose, myofibrillar proteins were extracted from Longissimus dorsi muscle and treated with DBD plasma for 0, 5, 10, 15, and 20 min to evaluate free sulfhydryl and carbonyl, FTIR, and DSC profiles as well as pH, color, foaming capacity and stability, emulsion capacity and stability, and water binding capacity of myofibrillar proteins. Evaluation of the chemical changes revealed that protein oxidation was the main event occurring during exposure to DBD plasma. Moreover, mild oxidation during the first 10 min of exposure was found to improve the functional properties of myofibrillar proteins such that significant (p < 0.05) increases were observed not only in foaming capacity but also in emulsion capacity and stability. However, the detrimental effects of severe oxidation on functional properties due to long-time exposure cannot be ignored. This is while long-time exposure was observed only to lead to significantly (p < 0.05) improved water binding capacity (WBC) (rising it from ~25% in the control treatment to ~92% in the 20-min treatment). The findings of this study can be beneficially exploited by the food industry toward appropriate treatment of myofibrillar proteins with non-thermal plasma.