Ultrasound-driven modulation of myofibrillar protein conformation promotes salt uptake and taste enhancement in marinated chicken breast

Enhancing salt diffusion and flavour development in dense muscle matrices remains a key challenge in poultry marination. This study aimed to explore how ultrasound-assisted marination modulates protein structure and improves salt uptake and flavour development in chicken breast meat. Ultrasound treatment (150–750 W) altered muscle microstructure by disrupting myofibrillar alignment, loosening fibres, and modifying surface properties. Moderate ultrasound power (300 W) significantly enhanced NaCl uptake and water retention without compromising structural integrity, as evidenced by increased protein solubility, reduced particle size, and greater surface hydrophobicity. Spectroscopy and microscopy analyses indicated conformational loosening, α-helix loss, and smoother surfaces of protein aggregates, all contributing to improved solute penetration and texture. In contrast, excessive power (≥600 W) led to β-sheet aggregation, fluorescence quenching, and tissue collapse, negatively affecting tenderness and water-holding capacity. Taste evaluation and amino acid profiling further confirmed that moderate ultrasound promoted umami perception while reducing sourness and astringency. These findings highlight the role of ultrasound-induced protein structural changes in improving marination efficiency and flavour quality, offering a practical basis for optimising ultrasound-assisted processing of poultry meats.