Mechanism of plasma-activated water promoting the heat-induced aggregation of myofibrillar protein from silver carp (Aristichthys Nobilis)

This work aimed to explore the underlying mechanism of plasma-activated water (PAW) promoting the heat-induced aggregation of myofibrillar protein (MP). The results of particle size and atomic force microscope indicated that PAW accelerated the aggregation of MP with PAW60 showing the densest and most homogeneous crosslinking morphology. Raman spectroscopy showed that about 4.11% of the α-helix in PAW60 changed to β-sheet during heating. The effects of PAW on the oxidation of MP were assessed in terms of sulfhydryl, disulfide bonds, carbonyl content and surface hydrophobicity. The amino acid composition revealed that the content of tyrosine dropped from 45.43 mg/g of PAW0 to 37.35 mg/g of PAW240, indicated that tyrosine in MP was converted to dityrosine by PAW. These results indicate that PAW promotes the oxidation of MP and further changes in intra- and inter-molecular interactions, which provides a theoretical basis for PAW promoting thermal aggregation of MP.