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How to analyze a food sample for possible bacterial contamination - Food that is involved in a minor outbreak (Oct/28/2010 )

Hello guys,
I must say my knowledge in Microbiology is at the rookie level. I have been assigned to write an article about the approach in detection of microorganisms in a contaminated food sold in a restaurant that health officials think is the source of the problem for sick patients. I have been given a situation where 5 patients that recently admitted in the hospital, all suffering from same problems, consumed a particular item in a local restaurant 24 hours before getting sick.

The food material that is responsible is known. Can any of you here please help me with how microbiologists get started on detecting what organisms are growing in the food? To my knowledge, it is purchasing the cooked food material, drop it in enrichment broth, then take the culture, plate it on different agars to screen for microorganisms. That is all I know. I am sure there is a lot more than that. I don't know if the detection methods necessarily need to be rapid, but I have been asked to come out with a step by step approach to detect. Please help me out experts.

-jonnychan-

hola, there is a system based in metabolic markers. they are coloured strips and itīs known as API system. Good luck

-protolder-

The question is difficult, because pages could be written on this topic and the methods used see here, but simple at the same time.
I do not know in what function and for what kind of publication you are to write the article, but for cases as the mentioned there are usually local/national authorities who routinely do such identifications. They know the (national) standards that need to be followed and what is - at least here in Europe important - are certified to do such tests, meaning that they have the knowledge, equipment and documentation to do the tests without the risk of environmental cross contamination. Therefore I would suggest you to consult the responsible authority and ask them for help. This will save you a lot of work, time and the frustration that you have not followed the required standard procedures.

-gebirgsziege-

jonnychan on Fri Oct 29 00:04:44 2010 said:


Hello guys,
I must say my knowledge in Microbiology is at the rookie level. I have been assigned to write an article about the approach in detection of microorganisms in a contaminated food sold in a restaurant that health officials think is the source of the problem for sick patients. I have been given a situation where 5 patients that recently admitted in the hospital, all suffering from same problems, consumed a particular item in a local restaurant 24 hours before getting sick.

The food material that is responsible is known. Can any of you here please help me with how microbiologists get started on detecting what organisms are growing in the food? To my knowledge, it is purchasing the cooked food material, drop it in enrichment broth, then take the culture, plate it on different agars to screen for microorganisms. That is all I know. I am sure there is a lot more than that. I don't know if the detection methods necessarily need to be rapid, but I have been asked to come out with a step by step approach to detect. Please help me out experts.



I think that it would be best for you to contact your national health institute that is given the task to check the food in different places..

Each country normally has a food and health institute that checks restaurants etc.. And I think they will be able to give you better information or more detailed information.


I am not sure they still use the "older" standard system (meaning plating and replating etc..) , on the more modern institutes they work with DNA probes now or and thats important: they use they experience to plate more direct (select wich medium that is needed..) The more experienced scientist are able to allready make some sort of detection based on what they see, hear or what the complaints are.. they are able to narrow it down allready.


Is this a school task by the way or?

-pito-

Your quote: think is the source of the problem for sick patients

Other possibilities...could it be bacterial toxin...thus organisms are not live? Could it be a non-micro contaminant as well?

-sgt4boston-