THE PASTEURIZATION OF MILK APPLYING OHMIC HEATING IN COMPARISON WITH CONVENTIONAL METHOD AND THE QUALITY ATTRIBUTES OF LACTOSE-FREE MILK
So far, there has been an increasing number of people with lactose intolerance reported in Thailand. The main objective was to determine the potential of applying ohmic method in the pasteurization of both normal and lactose-free milks. The lactose-free milk was prepared from the cow milk using lactase enzyme. The electrical conductivities of both normal and lactose-free milks obtained from various conditions
were measured applying ohmic heating apparatus. Furthermore, the chemical and physical properties of milk samples pasteurized at 63 °C for 30 min by conventional method and ohmic method were compared. It appeared that the electrical conductivities of milk samples were in the range of 0.635-1.230 S•m-1 indicating that they could be efficiently heated by ohmic method. Moreover, the electrical conductivities of normal
and lactose-free milks were insignificant different. There was no significant difference in aspects of protein content, total acidity and specific gravity between the milk samples pasteurized by conventional and ohmic methods. In summary, the ohmic method showed its potential for the milk pasteurization.
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