Study on the Extension of Shelf-life by Activation of Inherent Lactoperoxidase System in Raw Cow Milk

Effectiveness of lactoperoxidase in raw cow milk was studied to observe the increase in shelf-life. Lactoperoxidase system was activated within two hours after milking by the addition of hydrogen peroxide and potassium thiocyanate, then milk was kept at different conditions viz. refrigerated condition (5±2)°C, room temperature (25±3)°C and at (35±2)°C. The keeping quality of raw milk was determined by the acidity, which when reached 0.18 % as lactic acid, was considered spoiled. Results indicated that the lactoperoxidase system (LP-s) increased the shelf-life of raw cow milk kept at room temperature (25±3)°C and refrigeration temperature (5±2)°C significantly (p<0.05);however no significant increase in shelf-life was observed between the control and LP-s treated raw milk sample held at (35±2)°C. DOI: http://dx.doi.org/10.3126/jfstn.v7i0.10606 J. Food Sci. Technol. Nepal, Vol. 7 (57-60), 2012