What is best practice when sampling frozen meat for micro-test?

Hi all,

I wonder what the best practice is when it comes to take samples from frozen meat for micro-test. How can frozen and bulky meat be sampled as aseptically as possible while it is not temperature abused? Our QC tech leaves out frozen meat at room temperature while monitoring surface temperature and takes samples when the meat is more workable since it can be as hard as solid rock when frozen. I don't like this practice but I was told that there has been no problem and no space available in the cooler so we can't defrost the meat in there.

Any help or idea will be appreciated.

Hi all,

I wonder what the best practice is when it comes to take samples from frozen meat for micro-test. How can frozen and bulky meat be sampled as aseptically as possible while it is not temperature abused? Our QC tech leaves out frozen meat at room temperature while monitoring surface temperature and takes samples when the meat is more workable since it can be as hard as solid rock when frozen. I don't like this practice but I was told that there has been no problem and no space available in the cooler so we can't defrost the meat in there.

Any help or idea will be appreciated.

Dear Minyoung,

There are well-documented, official procedures for this within the microbiology field/text-books. They typically involve sterile tools for drilling/coring and sampling frozen foods.

It is also true that many small labs choose to short-cut (economise) by waiting for the surface glaze to disappear in order to facilitate cutting a portion of still frozen material. This obviously tends to limit ones options for a "random" sample. Have never seen a detailed evaluation of the possible errors involved but logically the outer surface will have a (much?) higher bacterial load. "Rare" steaks rely on such logic for safe consumption.

Rgds / Charles.C

MinYoung -
I agree with Charles about 'short-cut' methods. One question is: what are you trying to accomplish - finding a 'bug' if it is there, collecting data for export product, AVG microbial load per gram of product, surface 'contamination', supplier performance comparisons, etc. That then drives the sampling technique you have to use.

Since you are in the US, search the FDA and USDA FSIS websites. They both have micro sampling and analysis procedures that they use for 'official' samples.