Microwave irradiation promotes aggregation behavior of myosin through conformation changes

The aim of this work was to investigate the role of microwave on myosin aggregation during different heating process and to explore the potential relationship between conformation changes and physicochemical properties of myosin. Microwave heating lead to the increasing of turbidity of myosin, but this result was largely influenced by the temperature. Surface hydrophobicity were the dominant binding forces in the formation of myosin aggregation. However, the disulfide bonds play a much more important role in the protein aggregation forming in heat treatment at 60 and 90 degrees C. Circular dichroism revealed that microwave heating considerably altered the secondary structure of myosin. The gradual disappearance of negative peaks at 202 and 222 nm indicated that a significant decrease in alpha-helix formation. Particle size distribution and atomic force microscopy analyses demonstrated a more rapid myosin aggregation in response to the microwave treatment at 60 and 90 degrees C. These results helps to better understand the gel formation mechanism of surimi under microwave field and to improve myosin-based food quality by using microwave treatment.