Physical stability of infant milk formula made with selectively hydrolysed whey proteins

A whey protein ingredient, in which β-lactoglobulin was selectivity hydrolysed, was evaluated during manufacturing of infant formulae. Three model infant milk formula (IMF) powders were produced containing: non-hydrolysed (NH) proteins (60:40; whey proteins:caseins); partially hydrolysed (PH) caseins and whey proteins; and selectively hydrolysed (SH) whey proteins. After homogenisation, particle size (D[4,3]) of the SH formulae was similar (P > 0.05) to NH formulae and was significantly (P < 0.05) smaller than PH formulae. Prior to spray drying (∼55% w/w), the viscosity of SH formulae (14.8 ± 0.3 mPa s) was significantly lower (P < 0.05) than that of the NH (48.6 ± 0.8 mPa s) or PH formulae (27.6 ± 1.5 mPa s). Surface free fat, wettability and glass transition temperature of powders were not significantly (P > 0.05) different. IMF manufactured with SH ingredients have applications in high dry matter processes with potential for reduced energy costs in spray drying.