Uncovering the chemical bonding basis for ultrasound treatment-induced improvement in the molecular flexibility of myofibrillar proteins from low-salt meat batters with added methylcellulose

Abstract

Ultrasound (US) treatment modifies the construction of myofibrillar proteins (MPs) to improve the properties of low-salt meat batters (LMTs) with added methylcellulose (MC). This study investigated the correlation between the construction of MPs and their flexibility in LMTs adding different MC levels with US treatment. MPs exhibited the highest flexibility at 100 W, owing to a high concentration of myosin with hydrophobic interaction contents, e.g. 5.98 mg/mL in MPs from LMTs adding 0.4% MC. However, the ionic and disulfide bonds were reversed. SDS-PAGE revealed the depolymerization of MPs at low power (<100 W), whereas macromolecular aggregates were produced as the cross-linking of MPs at ≥100 W. This phenomenon is supported by the chemical bonding and flexibility of proteins. These findings demonstrate that appropriate US treatment induces the flexibility alteration of MPs from LMTs with added MC by modifying their construction and regulating bond interactions.