Performance of whey protein hydrolysate–maltodextrin conjugates as emulsifiers in model infant formula emulsions

Model infant formula emulsions containing 15.5, 35.0 and 70.0 g L−1 protein, soybean oil and maltodextrin (MD), respectively, were prepared. Emulsions were stabilised by whey protein hydrolysate (WPH) + CITREM (9 g L−1), WPH + lecithin (9 g L−1) or WPH conjugated with MD (WPH–MD). All emulsions had mono-modal oil droplet size distributions post-homogenisation with mean oil droplet diameters (D4,3) of <1.0 μm. No changes in the D4,3 were observed after heat treatment (95 °C, 15 min) of the emulsions. Accelerated storage (40 °C, 10 d) of unheated emulsions resulted in an increase in D4,3 for CITREM (2.86 μm) and lecithin (5.36 μm) containing emulsions. Heated emulsions displayed better stability to accelerated storage with no increase in D4,3 for CITREM and an increase in D4,3 for lecithin (2.71 μm) containing emulsions. No increase in D4,3 over storage was observed for unheated or heated WPH–MD emulsion, indicating its superior stability.