Calcium is present in casein micelles as bound calcium ions and as colloidal calcium phosphate (see Salts); sodium, potassium and magnesium ions are also bound to protein in the micelle together with.small amounts of citrate.

• 酷蛋白胶束中的外层有离子和磷酸钙复合物两种状态,胶束内还含有钠、钾、镁和少量柠檬酸盐。