Calcium fortification of a model infant milk formula system using soluble and insoluble calcium salts
Giovanni Barone, Jonathan O’Regan, Alan L. Kelly, James A. O’Mahony
Abstract
The impact of calcium fortification, delivered using different proportions of soluble (calcium chloride; CaCl2) and insoluble (micronised calcium citrate; CaCit) calcium salts, on physicochemical and thermal stability properties of a model infant milk formula (IMF) was determined. The IMF was formulated with a whey protein fraction dominant in α-lactalbumin and fortified with calcium (1500 mg L−1) using 70:30, 60:40, 50:50, 40:60 and 30:70 ratios of CaCit:CaCl2. Increasing CaCl2 levels decreased the net zeta-potential of IMFs from −41.0 to −22.1 mV and increased ionic calcium levels (1.44–6.99 mm). The apparent viscosity, especially at acidic pH (6.40), increased compared to the control with values ranging from 22.3 to 50.2 mPa s for ratios 70:30 and 30:70, respectively. In addition, mean particle size of the IMF increased, with values ranging from 2.19 to 43.4 μm. This study provides useful information in supporting next-generation fortification strategies of nutritional dairy-based products with calcium.