Impact of ultrasound on pumpkin seed protein concentrate hydrolysis: Effects on Alcalase, protein, and assisted reaction
Ana Flávia Coelho Pacheco, Letícia Bruni De Souza, Paulo Henrique Costa Paiva, Carini Aparecida Lelis, Érica Nascif Rufino Vieira, Alline Artigiani Lima Tribst, Bruno Ricardo de Castro Leite Júnior
Abstract
Ultrasound (40 kHz, 23.8 W/L) was applied (pH 7.5, 25 – 60 °C, up to 300 min) to Alcalase (protease) and pumpkin seed protein concentrate (substrate) as a pre-process or during proteolysis aiming to improve the hydrolysis rate, the final concentration of hydrolysates, and its solubility and in vitro antioxidant activity. The pre-process applied in enzyme and substrate increased the relative activity of the enzyme by 10.3 and 50.1%, respectively (p<0.05). Moreover, pre-sonication of protein and ultrasound-assisted hydrolysis provided up to 280% increase in the proteolysis rate and resulted in up to 24% higher concentration of soluble peptides, compared to conventional hydrolysis (p<0.05). Consequently, the hydrolysates obtained with ultrasound intervention had greater solubility (≤148.1%, p<0.05) and higher radical scavenging capacity than those produced through conventional hydrolysis. From the overall evaluation of the results, and considering the operational costs and equipment wear, we concluded that pre-sonication of pumpkin protein is the best strategy to enhance the generation of hydrolysates with better multifunctional properties.