TY - JOUR
T1 - Structural characterization of nanoemulsions stabilized with sodium caseinate and of the hydrogels prepared from them by acid-induced gelation
AU - Montes de Oca-Avalos, Juan Manuel
AU - Huck-Iriart, Cristián
AU - Borroni, Virginia
AU - Martínez, Karina Dafne
AU - Candal, Roberto Jorge
AU - Herrera, María Lidia
N1 - Publisher Copyright:
© 2020 The Author(s)
PY - 2020/11
Y1 - 2020/11
N2 - Hydrogels obtained by acidification with glucono-δ-lactone (GDL), starting from nanoemulsions formulated with different concentrations of sodium caseinate (1–4 wt%) or 4 wt% sodium caseinate and sucrose (2–8 wt%), were prepared with the aim of quantifying structural parameters of both, initial nanoemulsions and hydrogels after 2.5 h of GDL addition, using the Guinier-Porod (GP) or the generalized GP models. Gelation process was followed by performing in situ temperature-controlled X-ray small angle scattering experiments (SAXS) using synchrotron radiation. In nanoemulsions, the calculated radius of gyration for oil nanodroplets (Rgoil) decreased with increasing protein concentration and for the 4 wt% protein nanoemulsion, with increasing sucrose content. Calculated values of Rgoil were validated correlating them with experimental Z-average values as measured by dynamic light scattering (DLS). For hydrogels, radii of gyration for the sphere equivalent to the hydrogel scattering object (Rgsph) were close to 3 nm while correlation distances among building blocks (Rg2) were dependent on formulation. They increased with increasing contents of sodium caseinate and sucrose. Rg2 parameter linearly correlated with hydrogel strength (G’∞): a more connected nanostructure led to a stronger hydrogel.
AB - Hydrogels obtained by acidification with glucono-δ-lactone (GDL), starting from nanoemulsions formulated with different concentrations of sodium caseinate (1–4 wt%) or 4 wt% sodium caseinate and sucrose (2–8 wt%), were prepared with the aim of quantifying structural parameters of both, initial nanoemulsions and hydrogels after 2.5 h of GDL addition, using the Guinier-Porod (GP) or the generalized GP models. Gelation process was followed by performing in situ temperature-controlled X-ray small angle scattering experiments (SAXS) using synchrotron radiation. In nanoemulsions, the calculated radius of gyration for oil nanodroplets (Rgoil) decreased with increasing protein concentration and for the 4 wt% protein nanoemulsion, with increasing sucrose content. Calculated values of Rgoil were validated correlating them with experimental Z-average values as measured by dynamic light scattering (DLS). For hydrogels, radii of gyration for the sphere equivalent to the hydrogel scattering object (Rgsph) were close to 3 nm while correlation distances among building blocks (Rg2) were dependent on formulation. They increased with increasing contents of sodium caseinate and sucrose. Rg2 parameter linearly correlated with hydrogel strength (G’∞): a more connected nanostructure led to a stronger hydrogel.
KW - Guinier-porod model
KW - Hydrogel
KW - Nanoemulsion
KW - Nanostructure
KW - SAXS
UR - http://www.scopus.com/inward/record.url?scp=85105118654&partnerID=8YFLogxK
U2 - 10.1016/j.crfs.2020.03.010
DO - 10.1016/j.crfs.2020.03.010
M3 - Artículo (Contribución a Revista)
AN - SCOPUS:85105118654
SN - 2665-9271
VL - 3
SP - 113
EP - 121
JO - Current Research in Food Science
JF - Current Research in Food Science
ER -