| Abstract: | On the basis of FAO/WHO tolerance recommendations, slaughtered pigs were divided into groups with gamma-HCH residues ranging from 0.5 to 2.0 mg per kg and with DDT residues ranging between 0.5 and 5.0 mg per kg in fat. Groups with negative residue findings were formed for control. Some parameters of the biological value of lard were determined in pig back fat. The presence of DDT and gamma-HCH residues did not change the melting and congelation points of lard. The acid number was higher by 31%, the saponification number dropped by 2.6%, the iodine number by 7.6%, the level of palmito-oleic acid by 16%, linoleic acid by 15% and linolenic acid by 40% due to the presence of DDT residues in lard. In the lard containing gamma-HCH residues the acid number increased by 42%, the saponification number decreased by 3.6%, the number of 8.1%, the level of palmito-oleic acid by 14%, linoleic acid by 18% and linolenic acid by 30%. It has been inferred from the results that the presence of DDT and gamma-HCH residues in the organism of a pig reduces the biological value of lard owing to the probable alteration of fat metabolism. |
