Effect of roasting, boiling and microwaving cooking method on Doxycline residues in edible tissues of poultry by microbial method

Abstract

The purpose of this study was to determine the effects of different cooking processes like boiling, roasting and 
microwaving on Doxycline residues in chicken muscle, liver and gizzard tissues of broiler chickens. Each chick was 
fed by water and food with 0.1% of Doxycline in their drinking water for 5 consecutive days. Then, three locations 
were sampled aseptically from each carcass: Breast muscle, liver and gizzard. Doxcycline residue was analysed 
using microbial inhibition method by plates seeded with Escherichia coli. After doing different phases of the test on 
raw samples, the positive raw samples were cooked by various cooking procedures and we surveyed the cooked 
samples with a similar method again for the detection of residue. The results showed a reduction in the 
concentration of Doxycline residue after different cooking processes and a part of the residue in the boiling process 
were excreted from the tissue to the cooking fluid. Between the various agents affecting antibiotics residue after the 
cooking process, cooking time and temperature can play a major role in antibiotic residue reduction while cooking 
food. Regarding the results of this study, we can conclude that cooking processes do not guarantee a full 
elimination of these drugs present in condemned animals and it can only decrease its amounts.