Parallel Comparison of Functional and Physicochemical Properties of Common Pulse Proteins

Abstract The demand for more functional plant-based proteins has greatly increased. The objective of this study was to provide a systematic understanding of the functional properties and physicochemical features of protein isolates extracted from common pulses. Chickpea protein (ChPI) was much less soluble compared to other extracted proteins. Pigeon pea protein (PiPI) and lab extracted soybean protein (SPI) possessed excellent emulsification capacity and stability of 0.71-0.73 and 0.70-0.71 cm/cm, respectively. Most proteins had foaming capacities greater than 1.20 mL/mL, except for ChPI. Lentil protein (LPI-W), pea protein, and PiPI showed greater water absorption capacity of 4.9, 3.5, and 3.6 g/g than other proteins and good oil absorption capacity. Pigeon pea protein had the greatest gelation capacity, with a least gelation concentration of 80 g/L. ChPI had a higher thermal denaturation peak temperature (169 °C) than the other proteins (145 – 154 °C). Commercial SPI was much less functional compared to the lab extracted SPI, which was due to intensive protein denaturation during commercial processing. The amino acid profiles, SDS-PAGE patterns, secondary structure composition, and relative surface hydrophobicity were analyzed to help elucidate the functional features. This study provides useful information in selecting appropriate protein sources to achieve more desirable functional applications.