Effect of industry-scale microfluidizer system superfine-grinding on macromolecules of whole component pea and comparative effects on pea macromolecules

Industry-scale microfluidizer system (ISMS) was applied to superfine-grinding green peas at 30, 60, 90, 120 MPa for one pass, and 120 MPa for two passes to prepare whole component peas. The particle size distribution of whole component pea and the influence on starch, protein, and fiber in whole component peas was investigated. Particle size parameters including D_[4,3], D_[50] and D_[90] of whole component peas were reduced from 123.7, 119.0 and 269.0 μm to 33.9, 27.7 and 70.7 μm, respectively. Damaged starch content was greatly increased, and severe destruction of starch granules was observed by SEM morphology. The decrease in protein content and nitrogen element in the precipitate of ISMS-ground pea determined by Kjeldahl method and energy-dispersive X-ray spectroscopy indicated that more pea proteins were converted into soluble form. Confocal laser scanning microscope analysis found that fluorescence of pea fibers became bright, and its dimensions were enlarged, which indicated that dense fibers were separated to structurally loose form. Comparison with modifying pea macromolecules by ISM, there were difference in the degree of starch damage, increase in protein solubility, and fiber destruction in ISMS-ground pea. These phenomena implied that the superfine grinding effect of ISMS on green pea was mainly achieved by changing macromolecule components.