Morphology of soy protein isolate at oil/water and oil/air interfaces

Journal of the Brazilian Chemical Society

Barreto, Pedro L. M.¹  Soldi, Valdir¹  Zanetti-Ramos, Betina G.¹  Minatti, Edson¹  Fayad, Samira J.¹  Universidade Federal de Santa Catarina, Florianópolis, Brazil¹ 

关键词: interface;    emulsion;    protein;    surface;    microcapsules;   

DOI  :  10.5935/0103-5053.20130130

学科分类：化学（综合）

来源: SciELO

【 摘 要 】

Herein, the emulsifying properties of soy protein isolate (SPI) were highlighted by showing that the macromolecules undergo conformational changes when adsorbed at interfaces. The conformation of protein chains nested at the interfacial region of oil in water (o/w) emulsions by means of X-ray scattering (SAXS) and direct imaging (scanning electron microscopy (SEM)) techniques was investigated. The mean radius of gyration (Rg) for SPI (aq) is 20 nm and increases up to 30 nm in o/w emulsions; the proteins act as amphiphilic molecules by exposing their hydrophobic core to the oil and their hydrophilic amino acid residues to the water phase. By spray drying the emulsions, it was also possible to measure the size (Rg = 40 nm) and to evaluate the morphology of these proteins at the oil/air interface of the respective microcapsules. The walls of microcapsules are fractals of clustered objects with rough surfaces, which are smoothed by the presence of a cross-linking agent.

【 授权许可】

Unknown