Structural modification by high-pressure homogenization for improved functional properties of freeze-dried myofibrillar proteins powder

Abstract

To expand utilization of meat in various products, the structural, physicochemical and functional changes of water soluble myofibrillar protein powder (WSMP-P) were investigated as affected by high-pressure homogenization (HPH) intensities (0-20,000psi). HPH modified the structure of WSMP-P by random dissociation (myofibril and myosin polymer dissociation), partial unfolding and rearrangement (actin trimer formation), producing an amorphous protein structure with high thermal stability. α-Helix and β-turn conversion to β-sheet structures occurred at pressures above 15,000psi, suggesting an increase in myosin conformation flexibility with minor aggregation. Moreover, HPH was able to improve the water solubility and emulsifying properties of WSMP-P. This might be resulted from its unfolded flexible structure with submicron size and high surface net charge in aqueous suspensions induced by HPH. The findings regarding the improved functionality evidence potential of applying WSMP-P as protein supplements in formulated food or beverage at low ionic conditions.

Keywords: Freeze-dried powder; Functional property; High-pressure homogenization; Physicochemical property; Protein structure; Water soluble myofibrillar proteins.