Title
Effect of Hydrolysis Degree on Structural and Interfacial Properties of Sunflower Protein Isolates
Author
Jian Ren, Chun-Li Song, Hui-Ying Zhang, Narasimha-Kumar Kopparapu, Xi-Qun Zheng
Year
2016
Journal
Journal of Food Processing and Preservation
Abstract
The effect of different degree of hydrolysis (DH) by Alcalase on the structural and interfacial properties of sunflower protein isolates was investigated. Sunflower protein isolates were extracted from defatted sunflower flour and hydrolyzed by Alcalase by applying different DH (low [10%], medium [20%] and high [30%]). Size exclusion chromatography results showed that the sunflower protein hydrolysates with different low molecular mass distribution were detected. Circular dichroism analysis showed the hydrolysates possessed a decreased α-helix but higher β-turn and random coil structures. The analysis of intrinsic fluorescence spectra indicated a moveable tertiary conformation of the hydrolysates. In comparison with sunflower protein isolate, its hydrolysates showed higher foaming activity and emulsion stability, but the foams were unstable and the emulsifying activity index was decreased. The hydrolysis significantly modified the structural and interfacial properties of the sunflower protein isolate.
Instrument
J-815
Keywords
Circular dichroism, Secondary structure, Biochemistry, Food science