Effects of calcium chloride and sodium hexametaphosphate on certain chemical and physical properties of soymilk

ABSTRACT:  Soymilks with sodium hexametaphosphate (SHMP) (0% to 1.2%) and calcium chloride (12.50, 18.75, and 25.00 mM Ca) were analyzed for total Ca, Ca ion concentration, pH, kinematic viscosity, particle diameter, and sediment after pasteurization. Higher added Ca led to significant ( P ≤ 0.05) increases in Ca ion concentration and significant ( P ≤ 0.05) decreases in pH. At certain levels of SHMP, higher concentrations of added Ca significantly increased ( P ≤ 0.05) kinematic viscosity, particle diameter, and sediment. Increasing SHMP concentration reduced Ca ion concentration, particle diameter, and dry sediment content, but reduced kinematic viscosity of samples ( P ≤ 0.05). Adding SHMP up to 0.7% influenced pH of soymilk in different ways, depending on the level of Ca addition. When the pH of Ca-fortified soymilk was adjusted to a higher level, ionic Ca decreased as pH increased. There was a negative linear relationship between the logarithm of ionic Ca concentration and the adjusted pH of the soymilk. Ionic Ca appeared to be a good indicator of thermally induced sediment formation, with little sediment being produced if ionic Ca was maintained below 0.4 mM.