Effect of soybean oil content on textural, rheological, and microstructural properties of WBAXs-SPI emulsion-filled gels

Rheology, physicochemical properties, and microstructure of fish gelatin emulsion gel modified by γ-polyglutamic acid

In this work, the effect of the addition of γ-polyglutamic acid (γ-PGA) on the rheology, physicochemical properties, and microstructure of fish gelatin (FG) emulsion gel was investigated. Samples of the emulsion gel were evaluated for rheological behavior and stability prior to gelation. The mechanical properties and water-holding capacity (WHC) of the emulsion were determined after gelation. The microstructure of the emulsion gel was further examined using confocal laser scanning microscopy (CLSM). The results indicated a gradual increase in the apparent viscosity and gelation temperature of the emulsion at a higher concentration of γ-PGA. Additionally, frequency scan results revealed that on the addition of γ-PGA, FG emulsion exhibited a stronger structure. The emulsion containing 0.1% γ-PGA exhibited higher stability than that of the control samples. The WHC and gel strength of the emulsion gel increased on increasing the γ-PGA concentration. CLSM images showed that the addition of γ-PGA modified the structure of the emulsion gel, and the droplets containing 0.1% γ-PGA were evenly distributed. Moreover, γ-PGA could regulate the droplet size of the FG emulsion and its size distribution. These findings suggest that the viscoelasticity and structure of FG emulsion gels could be regulated by adjusting the γ-PGA concentration. The γ-PGA-modified FG emulsion gel also exhibited improved rheology and physicochemical properties. The results showed that γ-PGA-modified FG emulsion gel may find potential applications in food, medicine, cosmetics, and other industries.

Effect of variation in basic emulsion structure and polysaccharide content on the physicochemical properties and structure of composite-based emulsion gels as cube fat mimetics

This study aimed to reveal the effect of different basic emulsion structures (W/O/W and O/W) and polysaccharide additions on protein-polysaccharide composite-based emulsion gels utilizing soybean protein isolate, palm oil and konjac glucomannan. The results of texture profile, rheological tests, microstructure observations, and oral tribology showed that basic emulsion structures and konjac glucomannan addition had significant effect on the emulsion gels' properties, while the impact of konjac glucomannan addition was stronger. W/O/W double emulsion gels (DEG) exhibited lower oral friction coefficients and obtained higher scores for oiliness and juiciness during the sensory evaluation. However, O/W single emulsion gels (SEG) displayed a firmer texture and higher chewiness, a 29.62% and 49.57% increase compared to the DEG at 7% konjac glucomannan addition on the hardness and chewiness respectively. It has demonstrated the emulsion gels' potential as cube fat mimetics and feasibility of adjusting their properties by changing the basic emulsion structure.

Wheat bran arabinoxylan-soybean protein isolate emulsion-filled gels as a β-carotene delivery carrier: Effect of polysaccharide content on textural and rheological properties

This study aimed to investigate the effects of different wheat bran arabinoxylan (WBAX) concentrations (1, 2, 3, and 4 wt%) on the structural and physicochemical properties of WBAX-soybean protein isolate (SPI) emulsion-filled gels (EFGs) prepared using laccase and heat treatment. The properties of the various gels as well as their microstructure, rheology, and in vitro digestion behaviors were investigated. Results showed that WBAX-SPI EFGs with a 3 wt% WBAX concentration had a smooth and uniform appearance, high water holding capacity (98.5 ± 0.2 %), and enhanced mechanical properties. Rheological experiments suggested that a stronger and closer gel network was formed at 3 wt% WBAX concentration. Fourier transform infrared spectroscopy showed that laccase and heat treatment not only catalyzed the intramolecular crosslinking of WBAX and SPI, respectively, but also promoted the interaction between WBAX and SPI. Confocal laser scanning microscopy revealed that the WBAX gel network was interspersed within the SPI network. The interactions contributing to the gelation analysis revealed that chemical (disulfide bond) and physical (hydrogen bond and hydrophobic) interactions promoted the formation of denser EFGs. Furthermore, the WBAX-SPI EFGs provided a β-carotene bioaccessibility of 21.8 ± 0.6 %. Therefore, our study suggests that WBAX-SPI EFGs hold promising potential for industrial applications in the delivery of β-carotene.

Natural egg yolk emulsion as wall material to encapsulate DHA by two-stage homogenization: emulsion stability, rheology analysis and powder properties

The use of safe physical means to achieve egg yolk as natural carrier for active ingredients plays an important role in increasing the added value of egg yolk. In this paper, we prepared DHA-fortified egg yolk emulsion using high-speed shearing (HSS) only and HSS combined with high-pressure homogenization (HPH), respectively. HPH reduced particle size and zeta potential, allowing for better emulsion stability. After 14 days of storage, the encapsulation efficiency was 93.88% even with 15% (w/w) algae oil addition. Rheology analysis presented that HPH improve the viscoelasticity, indicating the enhancement of interaction force between droplets. Then, vaccum low-temperature spray drying (VLTSD) was used to produce powder, which allowed for minimal damage to the encapsulation structure according to scanning electron microscopy and the hydration properties of powder was improved. This work provides a new idea for using egg yolk to encapsulate DHA and improving the properties of egg yolk powder.