Title
Structure and dilatational rheological behavior of heat-treated lotus (Nelumbo nucifera Gaertn.) seed protein
Author
Xiangze Jia, Jianyi Wang, Xu Lu, Bingxin Zheng, Baodong Zheng, Zebin Guo
Year
2019
Journal
LWT
Abstract
The influences of heat treatment (60, 80 and 100 °C, 30min) on the structure and interfacial properties (adsorption at the oil−water interface and dilatational rheology of interfacial layers) of lotus seed protein (LSP) were evaluated. Heat treatment induced an increase in average diameter and surface hydrophobicity due to partial unfolding and aggregation of LSP. Specifically, the moderate heat treatment (60 and 80 °C) could significantly increase the net surface potential of LSP, while heating at 100 °C had no effect. Additionally, the lower surface pressure at long-term adsorption and similar dynamic interfacial rheology were observed as compared to native LSP. In contrast, heat treatment led to a higher diffusion and penetration rate of protein, as observed by a faster increase of surface pressure. Nevertheless, the viscoelastic properties of the adsorbed layer of LSP after heat treatment decreased and when the interfacial pressure was greater than 18 mN/m, the interfacial modulus showed a downward trend. These findings increase our understanding of the structural dependence of protein interface behavior and the application of heat-treated proteins in emulsion preparation.
Instrument
J-810
Keywords
Circular dichroism, Thermal stability, Secondary structure, Protein folding, Biochemistry, Food science