Physico-chemical and functional properties of milk protein concentrates obtained using a two-stage decalcification approach

Effects of decalcification (0–72%) through mixing ultrafiltration retentates of highly acidified and nonacidified skim milk on spray-drying and solubility of milk protein concentrate (MPC) were studied. Powder recoveries increased with decalcification. MPC solubility markedly improved at and above 13% decalcification. Comparison was then made with MPC manufactured directly from moderately acidified milk at a decalcification ratio of 28%, where MPC solubility was satisfactorily high and casein micelle structures were generally maintained. No marked differences were observed in calcium and casein distributions, micelle structures and hence MPC functionalities between the two approaches. After mixing retentates of highly acidified and nonacidified milk, serum calcium and caseins re-associated into micelles to reach an equilibrium similar to that obtained using the one-stage approach. The novel two-stage approach allowed for an efficient and precise manufacture of MPC with different decalcification ratios, and with comparable micelle structures and functionalities to those manufactured using the one-stage approach.