Detection of inhibitors in milk by microbial tests. A review

The demands concerning microbial inhibitor tests were subjected to marked changes during the last decades: It started with the claim of being able to detect contaminated milk which might cause problems during fermentation processes ('technological safety'). Due to the present day attention drawn to toxic and allergic hazards for numerous antimicrobials Maximum Residue Limits (MRLs) or safe/tolerance levels are fixed ('toxicological safety'). This means a variety of demands underlying permanent changes with respect to the 'detection pattern' which cannot be fulfilled by a single test. Within an Integrated Detection System microbial inhibitor tests play an important role as screening methods for those antimicrobials which can be detected with satisfactory sensitivities. This paper deals with some features of microbial inhibitor tests such as detection limits, performance susceptibility for interference factors, qualitative determination and standardization.