Effect of Soy Soluble Polysaccharide on the Stability of Soy-Stabilised Emulsions During In Vitro Protein Digestion

Abstract

This study investigated physicochemical properties of soy soluble polysaccharide (SSP) and pectinase-hydrolysed soy soluble polysaccharide (PH-SSP) from okara, the residue from soy milk production, and their influences when used as a fibre source in oil-in-water (o/w) emulsions. Although pectinase hydrolysed only the carbohydrate fraction in SSP, it resulted in the self-association of PH-SSP to the large-size aggregates. When PH-SSP was added to liquid emulsion containing 3.33% (w/v) rice bran oil and 3.75% (w/v) heated soy protein, it regulated the contents of protein in serum phase, sediment phase and at oil-water interface. The types and contents of soy proteins in the serum phase and sediment phase could be manipulated by pre-heating of soy proteins at 80°C for 30 min and the addition of PH-SSP. The presence of PH-SSP (0-6% w/v) induced different distribution of proteins to the sediment phase and subsequent in vitro protein digestion in the emulsion. Overall, this study proposed the means to design the distributions of proteins in different phases of o/w emulsion for different degrees of oil release, emulsion stability and protein-polysaccharide coacervation during the course of in vitro peptic and tryptic digestion.

Effects of water‐soluble soybean polysaccharide on rheological properties, stability and lipid digestibility of oil‐in‐water emulsion during in vitro gastrointestinal digestion

“…The higher viscous system at high concentration of SSPS may also retard mobility of digestive enzyme, and consequently, the rate of lipid digestion was less than low viscous system. The SSPS may bind bile acid and interact with lipase, thereby reducing enzyme activity (Fafaungwithayakul et al., ). Hence, reduction in lipid digestibility of SSPS‐stabilized emulsions might be depended on various factors, such as surface ability of SSPS on oil droplet surface and viscosity of system.…”

Stabilization of acidic soy protein-based dispersions and emulsions by soy soluble polysaccharides

“…They attributed this to differences in side chain composition, with the pectin containing charged sidechains and SSPS containing mostly neutral sidechains. Fafaungwithayakul, Hongsprabhas, and Hongsprabhas (2011) found that pectinase hydrolysis of SSPS could alter soy protein-based emulsion stability and proposed this as a novel means of modifying oil release, emulsion stability and proteinepolysaccharide coacervation during digestion.…”

The roles of soy soluble polysaccharide on the emulsion stability against stimulated gastric conditions and food complexes - a review

“…The results suggest that SSPMRP-stabilized emulsions might help to increase the citral amount in the intestine with its release in a controlled manner. These results are supported by Yang et al (2015) and Fafaungwithayakul et al (2011). Negatively charged SSP might attach to the positively charged SPI molecules via electrostatic attraction, thus providing the extra stabilizing effect.…”

“…At pH 7.0, heat treatment (80°C, 30 min) of SPI during emulsification might reduce the insoluble conservation formation between protein and PHSSP. This might be due to the unfolding of proteins and the exposure of hydrophobic and charged reactive groups of proteins for inhibition of aggregation (Fafaungwithayakul et al, 2011). At pH 7.0, emulsion stabilized by H-SPI with 2.0% PHSSP exhibited a slight increase of protein (0.57 to 0.13%) in the sediment phase, although most of the proteins were in the emulsion phase.…”

“…The sediment phase height of PHSSP stabilized emulsion was higher at pH 2.0 (near about stomach pH) than emulsions having pH 4.5 and 7.0. This might be due to result of associating flocculation via linkage of negatively charged PHSSP and positively charged SPI (Fafaungwithayakul et al, 2011). When the H-SPI was used in the emulsion, the sedimentation was low at pH 7.0.…”