Emulsifying Properties Of Whey Protein Research Articles

Interfacial and emulsifying properties of whey protein concentrate by ultrafiltration.

The aim of this study was to concentrate whey protein by ultrafiltration process, evaluating the pressure at 1-3 bar and temperature of 10-20℃. In the conditions that show the more protein concentration were evaluated the interfacial and emulsifying properties at pH 5.7 and 7.0. The whey concentrate at 10℃ and 1.5 bar showed the higher protein value 36% (w/w), with soluble protein of 33.82% (solubility of 93.94%) for pH 5.7 and 34% (solubility of 94.4%) for pH 7.0, respectively. The whey concentrate powder present particle size distribution between 0.4-110 um. The whey at pH 5.7 and 7.0 was not observed significant differences in the resistance parameters of the oil/water layer interface. The interfacial film formed by the proteins presented an essentially elastic behavior in both pH, and in pH 5.7 the emulsion was more stable with lower diameter droplets. The concentrate whey showed techno-functional properties (emulsification and solubility), which allow the use as ingredients in products of industrial interest in food products such as mayonnaise, ice cream, sauces, and others.

Effects of Bacillus subtilis transglutaminase treatment on the functional properties of whey protein

Whey proteins (WPs) modification can improve their functional properties. To assess the crosslinking characteristics of Bacillus subtilis transglutaminase (BTG), it was used to reacted with WPs (12%, w/v) (40 °C, pH 8.0) for 6 h and 12 h, respectively. Both particle size profile and sodium dodecyl sulfate polyacrylamide gel electrophoresis demonstrated that BTG treatment enhanced the molecular weight of WPs. Meanwhile, BTG crosslinking greatly increased (*P < 0.05) the foaming and emulsifying properties of WPs. Furthermore, the rheological evaluation indicated that the cross-linked WPs showed greater storage modulus and loss modulus in comparison to the native WPs, leading to the increased gel strength. Additionally, BTG-induced WPs gels exhibited significantly enhanced (*P < 0.05) textural properties and water holding capacity. These results suggested the potential of BTG to enhance the functional properties of many proteins in the food industry.

Liposomal vesicles-protein interaction: Influences of iron liposomes on emulsifying properties of whey protein

In this study, whey protein (WP) was used as a model protein to interact with ferrous sulfate liposomes (FL). The interaction between FL and WP was researched using circular dichroism, intrinsic fluorescence, surface hydrophobicity, free sulphydryl groups, Fourier transform infrared spectroscopy, zeta potential, particle size, and interfacial tension. These observations indicated that FL interacted with WP via electrostatic force, hydrophobic force, and hydrogen bonds. WP secondary structure and tertiary structure could be changed by the interaction between FL and WP. The emulsifying properties of WP were improved by the interaction between FL and WP. Emulsifying activity index and emulsifying stability index of WP in the presence of FL increased from 39.69 to 65.63 m2/g, from 28.63 to 101.55 min, respectively. And the WP-stabilized emulsion droplet size decreased from 1.64 μm to 0.78 μm in the presence of FL. However, the emulsifying properties of WP were also influenced by liposomal composition, pH, and temperature. The changes of WP emulsifying properties could be attributed to the effects of liposomes on WP secondary structure and tertiary structure, zeta potentials, and particle size. This work provides new insights into the application of liposomes in food.