Influence mechanisms of linoleic acid and oleic acid on the gel properties of egg yolk protein.

ABSTRACT

BACKGROUND: Gel property is among the crucial functional properties of egg yolk (EY), which determines the texture and flavor of EY products. In the present study, the effects of two unsaturated fatty acids [monounsaturated fatty acid oleic acid (OA) and diunsaturated fatty acid linoleic acid (LA)] on the gel properties of EY protein were investigated. RESULTS: Compared with the blank group, the addition of LA and OA (10-50 g kg-1) improved the gel hardness (from 270.54 g to 385.85 g and 414.38 g, respectively) and viscosity coefficient (from 0.015 Pa.sn to 11.892 Pa.sn and 1.812 Pa.sn, respectively). The surface hydrophobicity of EY protein increased to a maximum value of 40 g kg-1 with the addition of both fatty acids (39.06 µg and 41.58 µg, respectively). However, excess unsaturated fatty acids (≥ 50 g kg-1) disrupted the completeness of the gel matrix and weakened the structural properties of the EY gel. CONCLUSION: Both fatty acids improved the gel properties of EY protein. At the same addition level, OA was superior to LA in improving gel properties. The present study provides a theoretical underpinning for the sensible application of unsaturated fatty acids in improving EY gel properties. © 2024 Society of Chemical Industry.