Abstract:
The main objective of this project was to determine the effects of the addition of calcium chloride (CaCl2) on mineral balance and physico-chemical properties of goat’s and cow’s milk. Various concentrations (from 0 to 50 mM) were used to fortify milk samples, all equilibrated at pH of 6.66±0.01. The concentration of inorganic phosphate (Pi) decreased in serum when the concentration of CaCl2 is increased. This alteration resulted from the Pi participating in the micellar phase as a calcium phosphate, in both types of milk species. The decrease of Pi from diffusible phase to the micellar phase was more marked in serum containing 0 mM to 20 mM CaCl2 compared to higher CaCl2 concentrations. In addition, the aggregation temperature decreased by increasing the concentration of CaCl2. Goat’s milk samples seems to be more heat stable at lower concentrations of CaCl2, but similar heat stability than cow’s milk at higher added CaCl2 concentrations is observed. In terms of casein micelle size, the average size of casein micelles in goat’s milk was larger than that of cow’s milk. In both types of the milks, initially the size of casein micelle size decreased at lower concentration (from 0 to 10 mM) of added CaCl2 and then the particle size started to increase at higher CaCl2 concentrations. Moreover, the zeta potential values of milk samples increased with the increase in the amounts of CaCl2. The zeta potential of milk samples also decreases when the pH is increased from 6.2 to 7.2. The outcomes of this project can be used in the calcium-fortification of milks of different species, with the aim of improving human nutrition.