Improving the structure and properties of whey protein emulsion gel using soluble interactions with xanthan and basil seed gum.

ABSTRACT

Applying hydrocolloids in the structure of protein emulsion gel can improve its properties. Interaction of whey protein concentrate (WPC) (5%) with xanthan gum (XG) and basil seed gum (BSG) at different concentrations (0.2%, 0.4%, and 0.6%) was investigated to improve mechanical and structural properties of emulsion gel. Results illustrated that gums created a stronger structure around the oil droplets, which confocal images approved it. Also, the particle size decreased and uniformed by cooperating 0.6% gum in comparison with WPC (46.87 µm). The lowest and highest hardness values were observed in emulsion gel formed by WPC (1.27 N) and 0.6BSG WPC (3.03 N), respectively. Also, the increase of gum concentration had a positive on consistency parameter of texture, so the value was 11.48 N s in WPC emulsion gel and it reached 0.6BSG WPC (25.71 N s) and 0.6XG WPC (19.96 N s). Evaluating the stability of the treatments by centrifugation indicated that 0.6BSG WPC (89.10%) and 0.6XG WPC (74%) had the highest level of stability. Increasing gum concentration increased the consistency and viscosity. Also, the viscoelastic properties of emulsion gel improved by 0.6% BSG. The elastic modulus of the WPC, 0.6XG WPC, and 0.6BSG WPC emulsion gels at the same frequency (1 Hz) was 240.90, 894.59, and 1185.61 Pa, respectively. In general, the interaction of WPC solution with hydrocolloids, especially BSG, is suggested to prepare more stable and elastic emulsion gels.