Shrimp Oil-Enriched Mayonnaise Prepared Using Fish Myofibrillar Protein as a Substitute for Egg Yolk: Physical, Rheological, and Sensory Properties

The effect of SO (shrimp oil) at various levels (5, 10, and 15%) on the stability of mayonnaise was investigated. Droplet size (d32 and d43), polydispersity index, and microstructure results showed an upsurge in droplet sizes with augmenting level of SO in mayonnaise (5 to 15%) (p < 0.05). SO imparted a bright orange color to the mayonnaise as evidenced by increased a* and b* values with lower L* values (p < 0.05). Moreover, the impact of a fish myofibrillar protein (FMP) substitution for egg yolk (0, 25, 50, 75%) in mayonnaise containing SO (5% and 10%) was also studied. Increasing the level of FMP substitution in SO-added mayonnaise showed a dilution effect and reduced a* and b* values (p < 0.05). In addition, excessive FMP substitution up to 75% drastically increased centrifugal and thermal creaming indices, indicating lowered stability (p < 0.05). Nevertheless, with the augmenting FMP substitutions, the viscosity, texture, and rheological properties in mayonnaise became lower (p < 0.05). However, there were no differences in overall acceptability scores between 5% SO-added mayonnaise with 25% FMP substitution (SO5:FMP25) and 5% SO-added mayonnaise without FMP substitution (SO5:FMP0) (p > 0.05). A confocal laser scanning microscopic (CLSM) study revealed a smaller droplet and less aggregation in the SO5:FMP0 sample, compared to SO5:FMP25. The incorporation of SO and FMP substitution yielded the resulting mayonnaise, which met the requirements of a healthy food since SO is rich in PUFA and the replacement of egg yolk by FMP can contribute several health benefits. The incorporation of SO as well as FMP as substitution for egg yolk therefore has potential in the development of functional foods.