Characterization of lactose and derived products in dairy product industry effluents processing

Summary

The treatment of the effluents of dairy product industries containing lactose is done by a biological process, which reduces considerably the original amount of that sugar. Although the final residual content of lactose is small after treatment, it may cause the eutrophication and/or the superfertilization of the water, which provokes vegetation growth on the water surface, hindering the navigability and increasing the consumption of the dissolved oxygen necessary to the life of the fishes of the river or sea where the treated effluent is poured. In dairy industry, after proper initial processing steps of waste treatment, lactose, as it is water soluble, may still be present in the outgoing effluents. A complementary step by using organophilic clay adsorption, as a further treatment of these effluents, may enhance antipollution procedures, decreasing its final content in the effluents. The present paper deals with the characterization, by thermal analysis of different lactose products, which may be present in the different processing steps as it dissolves in water and then it is recrystallized from it, as well as after being adsorbed by organophilic clay from those effluents, which are very diluted lactose aqueous solutions.