Experimental (a) and calculated (b) calcium-ion activity of phosphates in 50 mmol·L⁻¹ CaCl₂ solution. ●, Na₂UMP before heating; ○, Na₂UMP after heating; ♦, Na₂HPO₄ before heating; ◊, Na₂HPO₄ after heating; ■, SHMP before heating; □, SHMP after heating; ▲, SP before heating; ∆, SP after heating; –·–, Na₂UMP; — —, Na₂HPO₄; - - - - - -, SHMP; ——, SP, resulting in CaUMP, Ca₃(PO4)₂, Ca₃(PO₃)₆, and Ca₆phytate, respectively.