Physicochemical properties of soy protein isolates-acacia gum conjugates

Protein-polysaccharide conjugates were generally prepared by dry-heating. However, it was time-consuming and the sample gained was inhomogeneous. A faster way of preparing protein-polysaccharide conjugates is needed. Accordingly, soy protein isolates (SPI)-Acacia gum (GA) conjugates prepared by the wet-heating method were studied in the present work. Physicochemical properties of SPI-GA conjugates were also determined. The results showed that the wet-heating method could improve the rate of the graft reaction of protein and polysaccharide. The solubility of SPI-GA conjugates was significantly (P < 0.05) higher than that of unreacted SPI-GA mixtures and SPI at the same pH values. The emulsion activity index (EAI) of the grafted SPI increased remarkably. Moreover, a significant (P < 0.05) improvement on the emulsifying stability index (ESI) was observed and emulsions with a smaller droplet size were obtained. No visible flocculation during extended storage (30 days) was observed. The time course of the development of the graft reaction of SPI with GA was also shown by SDS-PAGE.

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Characterizing the Structural and Functional Properties of Soybean Protein Extracted from Full-Fat Soybean Flakes after Low-Temperature Dry Extrusion

Molecules ◽

10.3390/molecules23123265 ◽

2018 ◽

Vol 23 (12) ◽

pp. 3265 ◽

Cited By ~ 3

Author(s):

Wenjun Ma ◽

Fengying Xie ◽

Shuang Zhang ◽

Huan Wang ◽

Miao Hu ◽

...

Keyword(s):

Functional Properties ◽

Soy Protein ◽

Activity Index ◽

Soybean Protein ◽

Stability Index ◽

Extrusion Temperature ◽

Emulsifying Activity ◽

Protein Isolates ◽

Soy Protein Isolates ◽

Structural And Functional Properties

The soy protein isolates (SPI) extracted from different extruded full-fat soybean flakes (FFSF), and their conformational and functional properties were characterized. Overall, the free thiol (SH) content of SPI increased when the extrusion temperature was below 80 °C and decreased at higher temperatures. Soy glycinin (11S) showed higher stability than β-conglycinin (7S) during extrusion. Results also indicated that the increase in some hydrophobic groups was due to the movement of hydrophobic groups from the interior to the surface of the SPI molecules at extrusion temperatures from 60 to 80 °C. However, the aggregation of SPI molecules occurred at extrusion temperatures of 90 and 100 °C, with decreasing levels of hydrophobic groups. The extrusion temperature negatively affected the emulsifying activity index (EAI); on the other side, it positively affected the emulsifying stability index (ESI), compared to unextruded SPI.

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Physicochemical properties of soy protein isolates-cyanidin-3-galactoside conjugates produced using free radicals induced by ultrasound

Ultrasonics Sonochemistry ◽

10.1016/j.ultsonch.2020.104990 ◽

2020 ◽

Vol 64 ◽

pp. 104990 ◽

Cited By ~ 2

Author(s):

Feng Xue ◽

Chen Li ◽

Benu Adhikari

Keyword(s):

Free Radicals ◽

Physicochemical Properties ◽

Soy Protein ◽

Protein Isolates ◽

Soy Protein Isolates

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Formación y estabilidad de emulsiones de aislados proteicos de soja con diferente contenido de sulfhidrilos libres Formation and stability of emulsions of soy protein isolates with different sulfhydryl content

Food Science and Technology International ◽

10.1177/108201320000600507 ◽

2000 ◽

Vol 6 (5) ◽

pp. 407-414 ◽

Cited By ~ 4

Author(s):

L.G. Santiago ◽

A.G. Bonaldo ◽

R.J. González

Keyword(s):

Soy Protein ◽

Activity Index ◽

Ph Effect ◽

Surface Concentration ◽

Coal Surface ◽

Emulsifying Activity ◽

Protein Isolates ◽

Soy Protein Isolates ◽

Effects Of Ph

This work evaluated the formation and stability of emulsions prepared with three soy protein iso lates with different sulfhydryl content (SHL) and at two different pHs (6.00 and 7.00). Solubility (Sol), emulsifying activity index (IAE), coalescence (%Coal), surface concentration of proteins (r), and ki netics of the creaming process were determined. The effects of pH and sample types or their interac tion were significant (p < 0.05) for the four variables. IAE was little enhanced by the SHL increment, while stability to coalescence decreased. Also, it was verified that Γ is negatively affected by the SHL increment. The pH effect on IAE depended on the SHL. When pH decreased, %Coale lowered and Γ increased. Emulsions destabilized by the floculation-creaming mechanism more slowly at pH 6.00 than at pH 7.00.

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