Evaluating Rapeseed Oil Bodies as an Egg Yolk Substitute in Mayonnaise: Effects on Nutritional, Sensory, and Rheological Properties

Although egg yolk is widely valued for its nutritional contribution and excellent emulsifying functionality in mayonnaise, its high fat and cholesterol content has increased interest in developing healthier and plant-based alternatives. This study investigated the influence of substituting egg yolk with various proportions of rapeseed oil bodies (ROB) on the physicochemical, sensory, and digestive properties of mayonnaise. Results showed that ROB substitution led to a significant decrease in fat (31.2%) and cholesterol (100%), indicating a notable nutritional improvement. Although the higher moisture content of ROB reduced viscosity and stability, the mayonnaise containing 28% ROB did not differ significantly in overall acceptability from regular mayonnaise. ROB substitution also affected color, resulting in a 7% higher L* value and 67.4% and 30.2% lower a* and b* values, respectively, due to the milky-white nature of ROB. Stability tests indicated that mayonnaise with ROB exhibited similar physical and thermal stability to traditional egg yolk-based mayonnaise due to the comparable emulsifying properties of ROB. The nutritional quality of the ROB-based mayonnaise was improved by enhancing the levels of unsaturated fatty acids, including oleic acid (18.4%), linoleic acid (31.7%), and alpha-Linoleic acid (8.8%). Rheological analysis revealed similar viscoelastic properties for both ROB-based and egg-based mayonnaise. Overall, these findings indicate that ROB is a viable emulsifier for egg yolk replacement in mayonnaise, offering a practical strategy for developing healthier emulsified foods. Further studies are required to optimize formulation parameters, assess long-term stability, and evaluate consumer acceptance to support potential industrial applications.