Physicochemical properties of enzymatically modified pea protein-enriched flour treated by different enzymes to varying levels of hydrolysis

Background and objectives Air-classified pea protein-enriched flour (PPEF) was modified with trypsin, Savinase, papain, and pepsin to achieve 2%-4% and 10%-12% degrees of hydrolysis, and the surface and functional properties of the hydrolyzed products were assessed. Findings Surface hydrophobicity increased from 13.3 to 48.5 A.U. with papain treatment. Surface charge became more electronegative from -12.6 to -19.0 mV with pepsin treatment. However, solubility of hydrolyzed PPEF at all pH values tested (4.0, 7.0, and 10.0), regardless of enzyme treatment, decreased. Low solubility of hydrolyzed proteins negatively impacted solubility-dependant functional properties: foaming properties and emulsifying properties decreased. However solubility-independent properties (water- and oil-holding capacity; WHC and OHC, respectively) improved with proteolysis, increasing from 0.6 g/g to 1.4-2.0 g/g and from 0.7 g/g to 1.0-1.5 g/g, respectively. Conclusions Papain treatment yielded the best results in terms of both OHC and WHC of PPEF. Significance and novelty The resultant hydrolyzates have potential for baked goods and processed meat applications because of their increased OHC and WHC.