Effect of the addition of an emulgel based on whey protein isolate-alginate-inulin complex on the physicochemical and textural properties of reduced-fat set yoghurt

Oil-in-water emulgels formed with canola oil and whey protein isolate:alginate-inulin ternary complex coacervates (TCC) were used as fat replacers (10-15% wt.) in a reduced-fat set yoghurt (RFY). The addition of the emulgel had a significant effect (P < 0.05) on RFY syneresis and better stability against whey expulsion compared to a full-fat set yoghurt (FFY). Microstructure in RFY added with emulgel showed denser packing structures in the protein lattice with filling behaviour of emulgel. The textural and rheological properties showed that the emulgel contributed to mimicking and modulating its performance like that of FFY. The complex elastic modulus (G*) indicates that higher emulgel content in RFY improved the strength of the gel, allowing it to achieve a behaviour like that of FFY. The addition of emulgel increased the protein (55.3-63.2%) and reduced the fat (30.1-42.9%) contents, allowing the development of more balanced foods with similar mechanical properties to an FFY.