A research submitted in partial fulfillment of the requirements for thedegree of Master of Science inFood Engineering and Bioprocess Technology, School of Environment, Resources and Development

Research Studies Project Report (M. Eng.) - Asian Institute of Technology,2015

This research study was conducted to determine the occurrence of E.coliand Salmonellain beef and to study their antibiotic resistance profiles. Beef samples (15) were collected fromTalad Thaimarket, Pathum Thani area, Thailand and analyzed through culture methods for possible contamination of E. coliand Salmonella.E. coliwas found in 9 out of 15 samples (60%), while Salmonella was found in 3 samples (20%). All 12 isolates were confirmed through biochemical tests which included: TSI, Indole test, Methyl red test, Voges Proskauer test, and Citrate test. Antibiogram analysis revealed that bacterial isolates were resistant against some tested antibiotics.E.coliresistance was recorded against Ampicillin, Amoxicillin and Tetracycline (44.44%), Sulfamethoxazole/Trimethoprim, Chloramphenicol (22.22%) and Streptomycin (11.11%). All Salmonellaisolates were resistant against Tetracycline (100%) and Chloramphenicol (33.33%).This study confirms the presence of E. coliand Salmonellain beef meat and their resistance towards common commercial antibiotics which may be potential threat to consumer{u2019}s health. Good hygienic practices during the slaughter processing, transport and storage of beef can reduce the contamination.