Investigation of Stability and Some Properties of Pickering Emulsions Containing Amaranth Protein Isolates Prepared with Sesame and Corn Oil

Nowadays, the necessity of using stable and high quality Pickering emulsions in the preparation of low-calorie foods has been considered by food industry researchers. In this research, the effects of oil type (sesame and corn) and its amount (20-70%) on some properties of Pickering emulsion containing amaranth protein isolates  (droplet size, creaming index, protein absorption, surface tension and color indexes) were investigated. The results showed that the diameter of emulsion droplets was in the range of 0.87 to 1.5 μm. Although the increase in the oil concentration caused a very significant increase (P <0.0001) in the diameter of the emulsion droplets, protein absorption, and b* index, a notable decrease (P <0.0001) was detected in the color indexes of L* and a*. In other characteristics of prepared emulsions, the rise in oil content from 20% to 50%, effectively increased the creaming index (P<0.005) and surface tension (P<0.0001), while in samples containing 70% oil, the mentioned properties decreased. Finally, it is concluded that the samples containing 70% corn oil or 20% sesame oil had the best emulsion properties.