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Heat stability of veterinary antibiotics in cow milk

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
Heat Stability of Veterinary Anbiocs in cow milk
Department of Food Hygiene, University of Veterinary Medicine, Budapest, Hungary

Antibacterials are used to prevent or treat infectious diseases in food-producing animals. The use of
antibacterial substances may result in the presence of residues in milk and other edible tissues especially
when withdrawal times are not observed. Anbacterial residues in milk may cause serious public health
hazards including allergenic reacons, disorders in the intesnal ora and have possible eect on the
emergence of anmicrobial resistance for anmicrobials used in human therapy. They may also have a
negave impact on starter cultures used in fermentaon processes in the dairy industry or preparing dairy
products at home.
Commission Regulation 37/2010/EC (1) established the maximum residue limits (MRLs) in milk and other
foodstuffs.
Concerning thermal stability of veterinary antibiotics in milk fair data are available (2,3,4). In connection
with the effect of boiling in household practice there are fewer information. The aim of this study was to
determine the heat stability of various veterinary antibiotic residues that may be present in the milk,
applying the temperature-time combinations that are used at home by consumers.


1. EU Commission Regulaon No. 37/2010 on pharmacologically acve substances and their classicaon regarding maximum
residue limits in foodstus of animal origin
                 
Food Chem. 
β-lactams in milkJ.
Dairy Sci. 
                 Journal of
Food Protecon-
5. Commission Decision of 12 August 2002 implemenng Council Direcve 96/23/EC concerning the performance of analycal
methods and the interpretaon of results
6. Guideline on the Bioanalycal Method Validaon, EMEA 2011

-


 



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--
 

 
 -
 


 
 

    
 
 
 - -
 
EU legislaon and guidelines
*not regulated in the EU, MRL Ref: hp://www.hc-sc.gc.ca/dhp-mps/vet/
mrl-lmr/mrl-lmr_versus_new-nouveau-eng.php

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

-



The studied compounds will not be completely eliminated by boiling. It seems from the results that
cloxacillin, tetracycline and trimethoprim shall be observed closely in raw milk even aer reaching the sub-
MRL levels. Keeping the milk at boiling temperature for two to ve minutes would allow variable decrease
in the amount of some compounds, but does not reduce totally the potenal risks to the consumers’
health.
The studied anbiocs showed rather mixed picture from heat stability aspects. In the group of beta-
lactams cloxacillin proved to be the most heat stable veterinary anbioc and cefoperazone has the lowest
heat stability
   

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Guideline on the Bioanalytical Method Validation
Guideline on the Bioanalytical Method Validation, EMEA 2011