SAMPLE COLLECTION

It is  important that samples are collected in a manner that ensures the integrity of the product being tested. The introduction of any microbiological or chemical contaminant at the time of sample collection can cause the results to be incorrect and therefore any remedial action that may be taken may at best be unnecessary or at worst be detrimental.

FOOD SAMPLE COLLECTION INSTRUCTIONS


  BULK COOKED and UNCOOKED FOOD  


1.
 Sterilise a suitable ladle in boiling water for 5 minutes and allow to cool in air so that the end doesn't touch any surfaces.

2.Choose a representative portion of the food and, using the ladle,scoop up at least 100 grams of sample.

3.If the food is to be cut using a knife and fork, this can be done as long as these are sterilised in a similar manner  to the ladle. 

4.Ensure the container is leak-proof and the sample has the details of your company or institution,type of food, batch number ,and the date and time of collection.

PACKAGED FOODS

1.Send an unopened package or unit, at least 100 grams, selecting the batch number required.


2.Depending on the usual storage temperature of the food  send to the lab at a similar temperature, as soon as possible.  

3.For cooked and uncooked foods send at 5 degrees C in an esky with a cold brick.

4.For packaged foods that are stale at room temperature send in an esky without a cold brick.

 

Send accompanying submission form stating requests required, limits of detection,full sample description, and full contact details.

NB Samples must reach the laboratory within 24 hours of collection.  

 

HYGIENE SWABS 

Hygiene swabs are generally taken from surfaces that have been cleaned on the previous day,and before the start of the next working day. If this is not practical,they can be taken directly after cleaning.

1.Use a sterile Amies swab following the instructions on the swab packet.

2.After aseptically removing the swab, moisten it in the sterile Amies transport gel in the tube, and swab the defined area, rotating the swab to absorb as much surface matter as possible.

Note: if the area to be swabbed is already visibly moist,the swab can be applied directly to the area without pre-moistening with Amies transport gel.

3.The defined area is usually 5x5 cm ,or 10x10 cm.

4.Insert the swab into its tube of sterile Amies transport gel.

5.Ensure the tube is labelled with details or code of the site from which it was taken.

6.Place it in an esky with a cold brick, along with a submission form outlining your company's details,the tests required, the date and time of sampling,the area swabbed, and any other relevant information you require on the report.

7. Arrange for the  esky to arrive at the lab in order for the swabs to be tested within 24 hours.

 

 

WATER SAMPLE COLLECTION INSTRUCTIONS

 It is important to collect water samples carefully,as this can be vital to the deductions that are drawn from the results.

Note:If samples for both microbiological and chemical testing are to be taken at the same time, the sample for microbiological testing should be taken first.

GENERAL POINTS ON SAMPLING PROCEDURE

* DO NOT open the bottle (or alternative sampling container) until immediately before filling.

* DO NOT rinse the bottle out before taking a sample,especially when sampling chlorinated water, as it contains a chlorine neutraliser (sodium thiosulphate).

*When removing the cap or stopper from the sample bottle, hold it in a manner that the fingers do not come into contact with its inside surface ,or with the neck of the bottle. Do not put the cap or stopper down in such a way that it will allow it to become contaminated.

*Hold the bottle near the base, rather than near the neck.

*Fill the bottle immediately with sample and replace the closure,observing the same precautions as for opening.

*DO NOT COMPLETELY FILL THE BOTTLE ,but leave about 2.5cm (1 inch) headspace (microbiological testing).

 

WATER COLLECTIONS FOR THERMOTOERANT COLIFORMS,E.COLI,PSEUDOMONAS or PLATE COUNTS

TAP WATER

1. Use a 250mL,screw-capped,sterile container containing chlorine inactivator.

2.Let tap water run for 30 seconds.

3.Uncap the jar and without touching the inside of it or the lid,fill within 2.5cm of the top with running tap water.

4.Secure lid aseptically.

SPA,POOL,DAM or CREEK WATER

1.Use a sterile 250/500mL screw-capped container containing chlorine inactivator.

2.Choose a deep part of the water source.

3.Uncap the jar and without touching the inside of it or the lid,quickly plunge the jar upside down into the water, then up again to obtain the sample from about elbow depth (approx 30 cm).

4.Fill the jar.

5.Some chlorine inactivator present in the jar will be lost with the above procedure. However,enough will remain in the container to be effective.

6.Secure lid aseptically.

LEGIONELLA &/or HETEROTROPHIC PLATE COUNTS

COOLING TOWERS

1.Use a 120mL ,screw-capped sterile jar containing chlorine inactivator.

2.Uncap the jar and without touching the inside of it or the lid, quickly plunge the jar upside down into the water,then up again to obtain the sample from the circulating water.

3.Care must be taken to avoid collection of sludge and other debris.

4.Secure lid aseptically.

WARM WATER SYSTEMS

As above,except collect circulating water from the storage vessel.

MIXING VALVES

1.Collect from the selected tap or shower head after it has been running about 30 seconds.

2.Avoid touching the inside of the jar or lid on anything.

3.Fill jar to within 1 cm of the lid to allow an air space for mixing.

4.Ensure lid is secured.

 

NOTE: Label samples with NAME, TYPE of WATER, DATE and TIME of COLLECTION.

* Specimens must reach the laboratory within 24 hours of collection.

*Store in fridge at 2 degrees C (not freezer), or in a cold esky during transit.