Leveraging ultra-micro crayfish shell powder to modulate protein digestion and health benefits in silver carp surimi

This study examined the effects of ball-milled crayfish shell powder (MD) and ball milling combined with irradiation crayfish shell powder (MID) on the digestion behaviors of silver carp surimi. During simulated digestion, surimi supplemented with crayfish shell powder exhibited reduced protein digestibility and hydrolysis. Furthermore, compared to surimi without crayfish shell powder, these samples showed larger digestate particle size, enhanced cholesterol-lowering activity, and increased release of essential amino acids. These changes were most significant (p < 0.05) in the MID-supplemented surimi. Peptidomics analysis revealed that crayfish shell powder reduced peptide release by inhibiting structural protein hydrolysis and enriching lipid-regulatory pathways. These effects were linked to the dense gel network formed by the crayfish shell powder, limiting enzyme accessibility. In conclusion, crayfish shell powder reduced protein digestibility, thereby potentially influencing the satiating effect of surimi while improving its nutritional profile, positioning it as a promising functional additive for health-promoting surimi food applications.