Preparation of iron bound succinylated milk protein concentrate and evaluation of its stability

• Preparation method of lyophilised milk protein–iron complex has been standardised.
• Succinylated milk protein shown improved iron binding ability than native protein.
• Yield from succinylated milk protein–iron complex was higher than native protein.
• Succinylated protein complex showed better processing stability than native protein.

Major problems associated with the fortification of soluble iron salts include chemical reactivity and incompatibility with other components. Milk protein concentrate (MPC) are able to bind significant amount of iron due to the presence of both casein and whey protein. MPC in its native state possess very poor solubility, therefore, succinylated derivatives of MPC (succ. MPC) were also used for the preparation of protein–iron complex. Preparation of the complex involved centrifugation (to remove insoluble iron), ultrafiltration (to remove unbound iron) and lyophilisation (to attain in dry form). Iron binding ability of MPC enhanced significantly (P < 0.05) upon succinylation. Stability of bound iron from both varieties of complexes was monitored under different conditions encountered during processing. Higher stability (P < 0.05) of bound iron was observed in succ. MPC–iron complex than native protein complex. This method could be adopted for the production of stable iron enriched protein, an organic iron source.