Application of rheology and interfacial rheology to investigate the emulsion stability of ultrasound-assisted cross-linked myofibrillar protein: Effects of oil phase types

This work was designed to illustrate the differences in the dispersed phase that affect the emulsion stability. The effect of oil types including soy oil, corn oil, rapeseed oil, sunflower oil, and flaxseed oil on the stability of the emulsion stabilized by modified MP (sonication after crosslinking treatment) was investigated. Results showed that the differences in fatty acid composition in the oil phase would affect the interaction between the oil phase and modified MP. Emulsion in the P-flaxseed group (with higher linolenic acid) showed lower TSI values, smaller protein-coated oil droplets, higher adsorbed protein content, storage modulus, and small elastic Lissajous curve area than other emulsion groups. While the P-rapeseed (with higher oleic acid) and P-sunflower (with higher linoleic acid) groups had large droplet sizes, poor emulsion stability, and rheological behavior. Correspondingly, the higher θo/w (86.97°), hf, π (21.55 mN/m), Kdiff, KR, Ed, E-π slope (3.22), and linear interfacial Lissajous plot in the P-flaxseed group indicated modified MP was preferred to adsorb on the surface of flaxseed oil to form an elastic-dominated interfacial protein film with higher deformation resistance. Furthermore, the poorer interfacial adsorption behavior and easily collapsed interfacial film further proved the poor emulsion stability of the P-rapeseed and P-sunflower groups. Therefore, differences in fatty acid compositions of oil phases impacted the interfacial adsorption characteristics of the modified MP, thereby influencing the emulsion stability.