Hello fellow,

if the cheese is made from raw milk, you will find a different diverse of microorganisms. if it made from heat treated milk it should contain specific species of microorganisms.

You may like to try  figuring out the millard reaction compounds.

I hope this answer can help.

Hi.

this link can help[ you

http://www.sciencedirect.com/science/article/pii/S0958694601000784

Thank you Haifa but it is a paper on  the effect ok heat treatment of cheese milk on proteolysis. I'm looking for a technique, starting from a cheese sample,  that allows to establish if cheese milk has been heat treated in origin.

Thank you Ebrahim for your suggestion, but I need a specific method, we are using now NMR; maybe something related to the enzymes denaturation. 

Hello Antonio,

I think that oxidase and peroxidase reactions could be used in the test.

In young cheeses I would just go looking for a wider variety of microorganisms (especially yeasts presence)

Otherwise, I believe the easiest way is to measure HMF by HPLC.

Check this:

http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2621.1999.tb15927.x/full#references

You most probably would want to build some sort of calibration curve for the specific type of cheese you are working with, since HMF extraction efficiency prior to assay may be matrix-dependent.

HMF concentration in pasteurized and non-pasteurized cheeses must be pretty different though. As long as you compare subjects within a single variety of cheese, extraction efficiency would not matter)

I hope this helps.

Thank you D.R. Sepulveda for your useful suggestion and for sharing such interesting paper.

The main problem for me is that we are investigating on low heat treatment such a thermization (68°Cx15"). In addition we have to find a method which can be used for  the legal aspects related to the protection of PDO cheeses.

Anybody has ever tried the NMR techniques?

Thank you Ahmed for your answer,

but I looking for an analytical tool with a large Reproducibility and Repeatability. This is very important because the tool should be used by the law in PDO cheeses protection.