Environmental Sampling in Meat and Food Processing
Sampling the meat & food processing environment for microorganisms is a common way to verify the sanitation of a facility. This video suggests methods to conduct this important verification activity.
Quality assurance personnel and operators of small meat processing establishments wanting to incorporate environmental sampling as part of HACCP verification.
How to sampling the food processing environment for microorganisms
- [Narrator] In this video, we will learn how to conduct microbiological sampling of the processing environment.
The safety and quality of the food we produce is critical to the ongoing success of our business.
Our customers expect a product that will not make them ill and will not prematurely spoil.
A critical part of producing safe food is ensuring that the plant environment is maintained in a way that will not contribute microbiological contamination to the finished product.
Whether processing uncooked meat products, such as raw sausage, or cooked meat products, such as hot dogs, a clean environment is necessary for the product to achieve the maximum shelf life.
A clean environment is also essential for pathogen control.
On raw products, a clean environment will help minimize pathogen levels, thus reducing the potential for consumers to come in contact with the pathogen.
For cooked products, pathogen control is essential, since the consumer will not cook the product to a point that eliminates pathogens such as listeria monocytogenes.
Therefore, pathogen control is essential and this is also a regulatory requirement.
To determine whether a processing environment has been properly cleaned, as well as to tell whether pathogens are present, environmental testing is conducted.
It is considered a verification procedure as part of a company's HACCP plan for sanitation, as well as listeria control.
For verification of sanitation, we use a swab procedure.
Needed for this are a sterile transport swab with moisturizer solution and diluent and a sterile form with two-inch-by-two-inch cutout.
A marker is also needed for marking the tube.
If swabs are going to be shipped, a cooler is needed with cold packs.
To begin with, lay the sterile form on the surface you intend to test.
Remove the moistened swab from the sheath without touching the swab itself.
Then wipe the surface inside the form with the swab, staying within the two-inch-by-two-inch area.
As you wipe, roll the swab slightly as you go back and forth across the two-by-two-inch area.
Then you will go in the opposite direction with the same swab, perpendicular to the swab motion just made.
You will be essentially swabbing the same surface twice.
It is important that you do not touch the swab surface.
Any contamination from your hand will get onto the swab and then give a false reading.
Once complete, place the swab back into the sheath.
Mark the test tube to designate the area where the swab was taken.
If testing is going to be completed in-house, transfer the swabs to the laboratory.
If it is being mailed, place the swabs in an insulated shipping container with a cold pack, seal the package, and ship for next-day delivery.
It is best to test swabs within 24 hours of sampling.
It is best to have a sampling map so that results can be trended over time.
When results come back, record the results for each of the designated areas.
A good result is generally less than 100 CFUs per four square inches, but lower may be better.
Areas that have high counts must receive corrective action.
For pathogen testing, our aim is to test a wider area.
For this, we use a sponge instead of a swab.
For sponge testing, you will need a sterile pre-moistened sponge, a pair of sterile gloves, and a cooler for transport.
A marker is also needed for marking the sponge bags.
Place the sterile gloves on your hands.
Open the bag with the moistened sponge and then remove the sponge from the bag.
Wipe the sponge on the area to be tested, covering a broad area.
Some use a standardized area of one-foot-by-one-foot.
Turn the sponge over and rewipe the same area, but rubbing in the opposite direction.
When completed, place the sponge back into the same bag.
Mark the bag with the designated area using the marker.
You can also add enrichment broth to the bag after the sponge has been inserted to start the analytical portion of the testing procedure.
Place the sponges in the cooler and return them to the lab.
If the testing is in-house, ensure the testing begins within 24 hours of taking the sample.
If the tests are to be shipped, place the bags with sponges into an insulated shipper along with a cold pack, seal the shipper, and send via next-day mail.
It is best to have a sampling plan so that areas can be designated and then tracked.
Record the results and take corrective action as needed.
Environmental sampling is an important verification procedure.
When properly done, swab testing can provide evidence that your facility is being cleaned properly.
Sponge testing for pathogens can help determine if there is a pathogen contamination issue in your facility.
Frequently Asked Questions