Physicochemical and functional properties of fermented pea and navy bean protein isolates

Background and Objectives There has been a significant increase in the use of fermentation for protein modification by the food industry. This research aimed to investigate the use of solid‐state fermentation (SSF) by Aspergillus oryzae NRRL 5590 on pea and navy bean protein isolates (PPI and NBPI, respectively) to enhance their physicochemical and functional properties. Findings The impact of fermentation was more profound on PPI than NBPI with a higher degree of hydrolysis achieved for the former (9.3% vs. 4.4%). Fermented PPI had significantly increased protein content, surface charge and hydrophobicity, solubility, and foaming properties, but decreased emulsion stability. For NBPI, modifications were only observed for surface hydrophobicity and water hydration capacity (WHC), which both increased after fermentation. Overall, navy bean proteins were less susceptible to protein hydrolysis than pea proteins upon fermentation, possibly due to the phaseolin protein in navy bean. Conclusions In summary, fermentation may be used to enhance the solubility and foaming properties of PPI and WHC of NBPI for their use as ingredients in applications where such higher functionalities are favorable. Significance and Novelty The results provide insights into pulse protein modification by bioprocessing, specifically fermentation, and opportunities for potential value‐added applications for pea and navy bean proteins.