Effects of explosion puffing on surimi-starch blends: Structural characteristics, physicochemical properties, and digestibility

This study investigated the influence of different explosion puffing pressures (0.6 MPa-1.0 MPa) on the structural characteristics, physicochemical characteristics, and digestibility of surimi-starch blends. With increased explosion puffing pressures, the starch granules attached to the protein network and bound to the protein increasingly tight. The results of X-ray diffraction and Fourier-transform infrared spectroscopy (FTIR) showed that explosion puffing destroyed ordered starch molecule chains resulting in a starch structure chaos. In addition, explosion puffing reduced the secondary structure number of surimi proteins by loosening intramolecular hydrogen bonds. The explosion puffing decreased the digestibility of puffed surimi-starch blends, while increased the resistant starch content. Maillard reaction in the puffing process led to the browning of the surimi-starch blends. the surimi-starch blends exhibited the optimal qualities with homogeneous pore structure, good color (70.11), excellent crispness (25.55 mm), desirable hardness (1967.57 Pa), and high expansion rate (398.85%) at explosion pressure 0.8 MPa. Our findings provide a reference for processing non-fried high-protein puffed food. [Display omitted] •The puffing pressure markedly affected the structure and texture of surimi-starch blends.•The binding of starch and protein became tighter as the puffing pressure increased.•The content of resistant starch in puffed surimi-starch blends increased.