Emulsion gel design for reduced-fat mayonnaise using yeast-derived single cell oil: Microstructural and rheological insights

This study aimed to use yeast-based Single Cell Oil (SCO), a sustainable lipid source, for the first time in mayonnaise production in response to the food industry's demands for reduced-fat and functional products. Emulsion gel systems with 5%, 10%, and 15% SCO were developed and their stabilities were analyzed over a 90-day storage period, benchmarked against a full-fat (71% sunflower oil) control (K1) and a conventional reduced-fat (15% sunflower oil) control (K2). The formulation with 15% SCO (M3) demonstrated comparable rheological and textural properties to the full-fat control (K1), meeting commercial mayonnaise standards despite a fat reduction of over 70%. This performance was supported by a dense, well-organized oil droplet distribution and a high emulsifying activity index (EAI: 197.54 +/- 1.13 m2/g). M3 displayed superior structural recovery under stress (Rec300%: 98.89%), alongside enhanced functional benefits, including the highest total phenolic content (310.21 mg GAE/kg) and strongest antioxidant activity (IC50: 20.46 mg/L; TAC: 46.41 mu mol Trolox/kg). Peroxide values indicated reduced lipid oxidation in SCO-enriched samples during 90-day storage. This study demonstrates that SCO is a highly effective, multifunctional ingredient for creating stable, reduced-fat mayonnaise with significant health and commercial potential, offering a sustainable alternative to conventional oils.