In this study, the effect of dynamic high pressure microfluidization at different pressures on the structural and functional properties of pea albumin and its complex with chlorogenic acid was investigated by measuring particle size, zeta potential, fluorescence spectra, infrared spectra, hydrophobicity, solubility and emulsification properties. The mechanism of the influence of chlorogenic acid on pea albumin in the binary system was explored. The results showed that after dynamic high pressure microfluidization treatment, the particle size and zeta potential of pea albumin firstly decreased and then increased. The microstructure, secondary structure and tertiary structure of pea albumin were changed. The solubility of small pea albumin particles was significantly increased by 42.37%, reaching 0.84 mg/mL under the action of shear force and other effects (P < 0.05), and the emulsification characteristics were also enhanced. The addition of chlorogenic acid changed the microenvironment of tryptophan residues in pea albumin, which led to significant changes in the structure of pea albumin. Meanwhile, it significantly increased the surface hydrophobicity and decreased the solubility of pea albumin (P < 0.05), and improved the solubility. This study provides an idea for pea albumin modification and a theoretical foundation for the development of high-value protein products.

In order to construct a suitable pea protein-based 3D printable meat analog system, this study explored the effects and mechanism of the addition of pea dietary fiber, gluten, gellan gum and glutamine transaminase on the 3D printing performance and product quality of mixture systems using one-factor-at-a-time and orthogonal array design methods. The results showed that the 3D printing performance, texture characteristics and product characteristics significantly changed depending on the concentration of each ingredient. Using the orthogonal array method, the optimal formulation that provided the best 3D printing performance was determined as 0.45%, 5:1, 0.4% and 1.2 U/g for pea dietary fiber concentration, ratio of pea protein to gluten, gellan gum concentration and glutamine transglutaminase dosage, respectively. After the optimization, the printing accuracy improved by 27.80%. The hardness of the printed sample after cooking was 3612.13 g, and the chewiness was 1540.27 g·mm. In addition, the texture characteristics were better than those of the unoptimized sample. The results of infrared spectroscopy and intermolecular force showed that the addition of the components significantly enhanced the hydrogen bond, disulfide bond and hydrophobic interaction in the system. Compared with three commercially available artificial meat samples, the optimized sample exhibited significant advantages in texture characteristics, cooking loss and water-holding capacity, which were related to the structure formed by 3D printing and the interaction among the components. This study provides theoretical guidance and a basis for the application of pea protein in 3D printed plant-based meat.

A physically cross-linked hydrogel was constructed by electrostatic interaction between chitosan (CS) and sodium hyaluronate (SH), and its texture properties, microstructure and functional properties were characterized. Meanwhile, the influence of loading with one of the probiotics Lactobacillus rhamnosus and Pediococcus acidilactici on texture characteristics and microstructure of the hydrogel was evaluated, the loading performance was analyzed, and the release mechanism of probiotic-loaded hydrogels in simulated gastroenteric fluid was explored. The results showed that CS-SH hydrogel, which was formed through electrostatic crosslinking, had good texture properties and bacteria-loading properties, and the loading capacity of 0.2 g (dry mass) of hydrogels for L. rhamnosus and P. acidilactici was 1.15 × 10⁹ and 1.25 × 10⁹ CFU, respectively. The probiotic-loaded hydrogel was continuously released in simulated intestinal fluid, and its release mechanism was through surface erosion. The maximum viable counts of L. rhamnosus and P. acidilactici in simulated intestinal fluid were 6.30 and 6.12 (lg(CFU/mL)), respectively. To sum up, CS-SH hydrogel is a potential probiotic delivery carrier that can be continuously released in simulated intestinal fluid. This study provides theoretical guidance and a research basis for the application and mechanism of action of physically crosslinked hydrogels in the field of probiotic loading.

The objective of this study is to investigate the mechanism of the modification of pea protein isolate (PPI) by transglutaminase (TG) in combination with dynamic high-pressure microfluidization (DHPM) and to clarify the applicability of the modified PPI in Pickering emulsion. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy showed that the morphology of PPI particles became more uniform after the modification. The degree of crosslinking with TG increased, and the tertiary structure of protein molecules changed. In addition, the surface hydrophobicity and endogenous fluorescence of PPI decreased, the emulsifying properties improved and the average particle size decreased. The Pickering emulsion stabilized by the modified PPI had improved stability and emulsifying capacity, and the best emulsion stability was observed at 120 MPa. TG-DHPM modification could provide a feasible method for the application of PPI in Pickering emulsion. This study provides an experimental basis for the development of high-performance Pickering emulsion systems and is of significant reference value for the functional modification of natural proteins.