TY - JOUR
T1 - Disulfide cleavage to improve interfacial behavior and emulsification properties of oat protein
AU - Li, Runnan
AU - Xiong, Youling L.
N1 - Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2023/3/15
Y1 - 2023/3/15
N2 - Disulfide bonds play an essential structural role but may hinder the molecular flexibility and functionality of proteins. The present study investigated the effect of disulfide cleavage on emulsifying activity of oat protein isolate (OPI). Four reducing agents tested (dithiothreitol, ascorbic acid, cysteine, and sodium bisulfite) except ascorbic acid disrupted inter-subunit S[sbnd]S bonds of OPI (up to 90 %) in a dose-dependent manner. Emulsification properties were measured specifically on cysteine-modified OPI, and the results showed increased emulsifying activity up to 37 % after subunit dissociation, which exposed hydrophobic groups and loosened the structure. In particular, emulsions formed by cysteine-treated OPI (1.7 to 6.7 mM/mg protein) displayed a superior interfacial protein coverage (0.170 m2/mg compared to 0.092 m2/mg for control) and reduced emulsion particle size (from 4722 to 2238 nm). The application of cysteine as a structure-modifying food additive can broaden the utilization of oat protein in emulsion-based food products.
AB - Disulfide bonds play an essential structural role but may hinder the molecular flexibility and functionality of proteins. The present study investigated the effect of disulfide cleavage on emulsifying activity of oat protein isolate (OPI). Four reducing agents tested (dithiothreitol, ascorbic acid, cysteine, and sodium bisulfite) except ascorbic acid disrupted inter-subunit S[sbnd]S bonds of OPI (up to 90 %) in a dose-dependent manner. Emulsification properties were measured specifically on cysteine-modified OPI, and the results showed increased emulsifying activity up to 37 % after subunit dissociation, which exposed hydrophobic groups and loosened the structure. In particular, emulsions formed by cysteine-treated OPI (1.7 to 6.7 mM/mg protein) displayed a superior interfacial protein coverage (0.170 m2/mg compared to 0.092 m2/mg for control) and reduced emulsion particle size (from 4722 to 2238 nm). The application of cysteine as a structure-modifying food additive can broaden the utilization of oat protein in emulsion-based food products.
KW - Cysteine
KW - Disulfide bonds
KW - Emulsification properties
KW - Oat protein
KW - Reducing agents
UR - http://www.scopus.com/inward/record.url?scp=85139597654&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85139597654&partnerID=8YFLogxK
U2 - 10.1016/j.foodchem.2022.134511
DO - 10.1016/j.foodchem.2022.134511
M3 - Article
C2 - 36240566
AN - SCOPUS:85139597654
SN - 0308-8146
VL - 404
JO - Food Chemistry
JF - Food Chemistry
M1 - 134511
ER -