Ultrasound-Assisted Enzymatic Extraction of Pinus pumila Nut Protein: Effects on Yield, Physicochemical and...

Pinus pumila nuts are renowned for their oil, which is abundant in unsaturated fatty acids. Nevertheless, the utilization of their oil meal has been constrained by the dearth of effective deep processing technology. To promote the use of Pinus pumila nut protein and environmentally friendly extraction techniques in the food industry, this study used ultrasound-assisted enzymatic (papain) to extract Pinus pumila nut protein (PUEP). The solid-liquid ratio significantly affected the protein yield, and the PUEP yielded up to 28.89%. Particle size, zeta potential, morphology, and color of PUEP are significantly different from traditional protein. The decrease in sulfhydryl content, the increase in the relative content of β-turns, and the increase in surface hydrophobicity significantly improved the functional properties of PUEP. There were no significant differences in thermal stability, amino acid composition, or molecular weight. PUEP extracted by ultrasound-assisted enzymatic extraction has a high extraction rate and excellent functional properties. In-depth analysis of the physico-chemical and nutritional properties of PUEP can help expand its use in the food industry.