Enhancing the quality of milk fat-free yogurt with vegetable oil emulsion stabilized by pea protein and steviol glycoside complexes

This study investigated the effects of soybean oil emulsions stabilized by pea protein isolate (PPI; 2%) and steviol glycosides (STE; 0.1%-0.8%) on the physicochemical, rheological, microstructural, and sensory properties of fat-free yogurt. Compared with the control fat-free yogurt, yogurts containing emulsions exhibited smaller particle size, higher water-holding capacity, improved textural parameters, and enhanced viscoelastic properties. Analysis of volatile compounds revealed a more diverse and concentrated profile of flavor compounds in the emulsion-containing yogurts relative to the control. These enhancements were accompanied by a brighter visual appearance and higher sensory acceptance scores. The quality of the emulsion-based yogurts was dependent on STE concentration, with measured parameters demonstrating STE concentration-dependent improvements. Yogurt formulated with the emulsion containing 0.4% STE showed the best overall quality, characterized by the most desirable texture, color, rheological properties, and the richest volatile compound profile. In conclusion, PPI-STE emulsion serves as an effective ingredient for improving the quality of fat-free yogurt and offers a promising strategy for producing high-quality dairy products.